Montr Signage

Distributed signage, in production

A Rust playback client and a Node.js/TypeScript control server driving up to 25 concurrent displays over WebSocket, with an automated multi-platform release pipeline in GitHub Actions. Running in production across Budget lobby displays.

Why Rust on the player

The playback client is the part that cannot fail quietly. A signage screen that crashes does not page anyone; it just shows a desktop, or nothing, in a customer lobby, potentially for days before someone mentions it.

Rust was chosen for the client specifically because that process has to run for weeks unattended while driving video through mpv. Memory safety and predictable resource behaviour matter far more there than development speed. The control server, where the iteration actually happens, is Node and TypeScript.

Splitting the two languages along that line was the central design decision: the boring, long-running, must-not-leak component in Rust; the part that changes often in TypeScript.

Coordination

WebSocket keeps the displays in sync with the server and makes the connection state observable. A display that has dropped off should be visible as dropped off, not silently showing yesterday's content.

Twenty-five displays is comfortably past the point where you can check them manually, which is what forced a real control plane rather than a pile of individually configured machines.

Release pipeline

Multi-platform builds run automatically through GitHub Actions. Pushing an update to two dozen displays by hand is the kind of task that gets skipped, and skipped updates are how a fleet drifts out of a known state.

Source is on GitHub.