diff --git a/README.md b/README.md
index f188226..34c5f68 100644
--- a/README.md
+++ b/README.md
@@ -8,14 +8,23 @@
 * gettext
 
 
+## Code formatting
+
+In order to have a single Python coding style, please use [black](https://github.com/psf/black). However, auto-generated files and parts of external projects should not be reformatted.
+
+```
+$ black $(find . -type f -name "*\.py" -not -path "*/migrations/*" -not -path "./static_extra/bulma/*" -print)
+```
+
+
 ## Quick-start (development)
 
 ```
-git clone https://git.khaganat.net/Tycho/khaganat-web.git khaganat-web
-cd khaganat-web
-vim .env
-PIPENV_VENV_IN_PROJECT=1 pipenv --three update
-pipenv run ./manage.py compilemessages
+$ git clone https://git.khaganat.net/Tycho/khaganat-web.git khaganat-web
+$ cd khaganat-web
+$ vim .env
+$ PIPENV_VENV_IN_PROJECT=1 pipenv --three update
+$ pipenv run ./manage.py compilemessages
 ```
 
 When editing the `.env` file, you should at least set `KHAGANAT_SECRET_KEY` to a random value, `KHAGANAT_DEBUG` to `"True"` and `KHAGANAT_HOSTNAMES` to `"localhost"`.
@@ -23,21 +32,21 @@ When editing the `.env` file, you should at least set `KHAGANAT_SECRET_KEY` to a
 To run this web application, you need a database. The simplest way is to download the one from the test server (`scp cipra.khaganat.net:/var/www/khaganat-web/db.sqlite3 db.sqlite3`). If you really want to start from scratch, you have to run the following commands:
 
 ```
-pipenv run ./manage.py migrate
-pipenv run ./manage.py createsuperuser
+$ pipenv run ./manage.py migrate
+$ pipenv run ./manage.py createsuperuser
 ```
 
 In order to display the Khaganat theme, you have to install bulma and build it :
 
 ```
-pipenv run ./manage.py bulma install
-pipenv run ./manage.py bulma build
+$ pipenv run ./manage.py bulma install
+$ pipenv run ./manage.py bulma build
 ```
 
 Now that everything has been set-up, you may run Django's internal debug server.
 
 ```
-pipenv run ./manage.py runserver
+$ pipenv run ./manage.py runserver
 ```
 
 If you created the database from scratch, Django will show an error when visiting the home page. To fix it, you need to go to `/admin/` and create a page with the `default` flag on.
@@ -82,11 +91,11 @@ You can set the following variables in the `.env` file:
 ## Quick update
 
 ```
-cd khaganat-web
-git pull
-pipenv --three update
-pipenv run ./manage.py migrate
-pipenv run ./manage.py compilemessages
+$ cd khaganat-web
+$ git pull
+$ pipenv --three update
+$ pipenv run ./manage.py migrate
+$ pipenv run ./manage.py compilemessages
 ```
 
 If you are not in a development environment (runserver), you also have to run `pipenv run ./manage.py collectstatic --clear --noinput` and may have to restart the WSGI server.