diff --git a/README.md b/README.md
index 995fcca..68405be 100644
--- a/README.md
+++ b/README.md
@@ -36,3 +36,9 @@ Cette branche démarre d'une installation toute prête de la demo Symfony. La db
   * `$ mv myproject/* . && mv myproject/.* . && rmdir myproject`
   * `composer require annotations twig orm form form validator maker-bundle security-csrf \
     && composer require --dev profiler`
+  * Adapt querystring in `./app/.env`:
+    ```
+    --- DATABASE_URL="postgresql://db_user:db_password@127.0.0.1:5432/db_name?serverVersion=13&charset=utf8"
+    +++ DATABASE_URL="postgresql://postgres:secret@db:5432/postgres?serverVersion=12&charset=utf8"
+    ```
+  * Create database schema: `bin/console doctrine:schema:create`
diff --git a/app/.env b/app/.env
index 7214849..6f32620 100644
--- a/app/.env
+++ b/app/.env
@@ -24,5 +24,5 @@ APP_SECRET=d6c584c628f4a555632b6e2c1382502a
 #
 # DATABASE_URL="sqlite:///%kernel.project_dir%/var/data.db"
 # DATABASE_URL="mysql://db_user:db_password@127.0.0.1:3306/db_name?serverVersion=5.7"
-DATABASE_URL="postgresql://db_user:db_password@127.0.0.1:5432/db_name?serverVersion=13&charset=utf8"
+DATABASE_URL="postgresql://postgres:secret@db:5432/postgres?serverVersion=12&charset=utf8"
 ###< doctrine/doctrine-bundle ###