Update README.md

README.md

@@ -1,9 +1,33 @@
 # Archifiltre statistics
 
-## Run the app
+Archifiltre statistics provides statistics about several Archifiltre metrics. The data comes from our app and website (via Matomo), GitHub and YouTube. We rely on Node.js, Express and TypeScript.
 
-Use the following command:
+## Launch the app
+
+First, create a `.env` file based on `.env.example`. You will need API keys for YouTube, GitHub and Matomo.
+
+Then, to install the project's dependencies, run the following command:
+```
+yarn
+```
+
+Finally, use the following command to run the app:
 ```
 yarn start
 ```
 
+By default, the server will run on `localhost:3000`
+
+## Run tests
+
+To run the tests, use the following command:
+```
+yarn test
+```
+
+## Run linter
+
+To run the linter, use the following command:
+```
+yarn lint
+```