Laravel Octane keeps the bootstrapped app loaded in memory, which can scale to thousands of requests per second for the toggling of cells. A separate script starts a Swoole HTTP server to make async I/O work in PHP for serving long-lived SSE connections. The event stream is compressed using gzip by the web server (standard Nginx). The app uses Redis pub/sub for real-time messaging, and a Redis key-value store for state persistence. Rate limiting on the server helps prevent automated bots causing too much havoc.

Finally, reactivity is powered by Datastar with one event listener and one long-lived SSE connection to the backend.

It all runs on a €4 Hetzner VPS.