Pulse — Node.js Realtime Server (WebSocket)

Pulse requires Node.js 18 or higher and has a single runtime dependency — the ws library. It uses native Node.js http, so no framework, no build step, and no transpilation is needed. Just clone, install, and run.

Pulse is built directly on Node's native http module and is not designed to plug into Express or similar frameworks out of the box. It runs as a standalone server, so the recommended approach is to run it as a separate service alongside your existing backend.

You get the full ESM server source, configuration via environment variables, three REST endpoints (/api/health, /api/stats, /api/rooms), and a polished three-pane demo web client built in vanilla JS with auto-reconnect. Everything runs on a single port with no additional setup.

Each room maintains a configurable ring buffer of past messages. When a new client joins a room, the history is automatically replayed to them, so they get immediate context without any extra client-side logic.

Yes — Pulse includes per-connection rate limiting, payload validation, and a heartbeat liveness check that automatically terminates dead sockets. Rooms are also created and cleaned up on demand, preventing stale state from accumulating.

Pulse is entirely self-hosted — you run and own the server on your own infrastructure with no third-party SaaS dependency. As a source-code product, you can read, modify, and extend it to fit your specific application needs.