It now does something useful

README.md

@@ -1,3 +1,40 @@
 # PREreview COAR Notify
 
-⚠️ This repo doesn't yet do anything useful.
+The source code for PREreview’s [COAR Notify] integration.
+
+## Development
+
+<details>
+
+<summary>Requirements</summary>
+
+- [Docker]
+- [Docker Compose]
+- [GNU Make]
+- [Node.js]
+- Unix-like operating system
+
+</details>
+
+### Running the app
+
+To build and run the app for development, execute:
+
+```shell
+make start
+```
+
+You can now access the app at <https://localhost:3000>.
+
+You will also have a `.env` file. This file contains environment variables controlling specific behaviours, including credentials for accessing external services.
+
+## Operations
+
+Once it passes CI, we deploy every commit on the `main` branch, which [Fly.io] hosts.
+
+[coar notify]: https://www.coar-repositories.org/notify/
+[docker]: https://www.docker.com/
+[docker compose]: https://docs.docker.com/compose/
+[fly.io]: https://fly.io/
+[gnu make]: https://www.gnu.org/software/make/
+[node.js]: https://nodejs.org/