CC2 Commander

A self-hosted web dashboard for the Elegoo Centauri Carbon 2. One Bun service holds the printer's single MQTT slot and fans it out: to browsers over a WebSocket, to Mainsail or Fluidd over a Moonraker-compatible API, and to Prometheus.

What it does

• Live dashboard: temperatures, fans, speed and flow, toolhead position, Canvas/AMS spools and the camera, pushed as the printer reports them.
• Print control: start, pause, stop, move, home, temperature presets, LED, emergency stop. Controls that need an idle printer disable themselves when it isn't.
• Files: browse local and USB storage with thumbnails, upload, print, delete.
• 3D gcode preview: Three.js toolpath with layer-follow and nozzle tracking.
• Filament dryer: uses the printer's own heated bed, and the timer lives in the service, so closing the tab cannot leave a hot bed with nothing to turn it off.
• History, reports, timelapse: past prints, PDF reports with charts, video download.
• Telegram notifications: print events, progress, camera snapshots.
• Moonraker & OctoPrint APIs: point Mainsail, Fluidd, KlipperScreen or an OctoPrint client at it.
• Prometheus metrics at /api/metrics/prometheus.
• Works on a phone: below 700px the grid becomes a one-card focus rail. Installable as a PWA.

The phone gets a one-card focus rail instead of the grid. The dryer runs in the service rather than in a tab, so closing the page does not leave the bed hot.

Run it

Save this as docker-compose.yml, set your printer's address, and docker compose up -d:

services:
  cc2-commander:
    image: ghcr.io/gren-95/cc2-commander:latest
    container_name: cc2-commander
    restart: unless-stopped
    ports:
      - "8088:8088"   # web UI, API and WebSocket
      - "7125:7125"   # Moonraker compatibility API
    environment:
      PRINTER_IP: "192.168.1.150"
    volumes:
      - ./elegoo-data:/app/data

Then open http://localhost:8088. The printer has to be in LAN-only mode.

That is the whole minimum. Passwords, Telegram, Home Assistant, camera overrides, image tags and every other variable are in docs/configuration.md.

The docker-compose.yml in this repository is deliberately different: it builds from the checkout instead of pulling, because if you have the source, building what is in front of you is the thing that cannot be stale.

Develop

bun install
bun run dev      # builds, serves on :8088, rebuilds on change
bun run gates    # lint, typecheck, dead code, build, unit + browser tests

There is also a container that keeps node_modules, the browsers and every generated directory off your machine. See docs/development.md.

Documentation

Configuration	Docker, environment variables, auth, volumes, ports, deploying
Development	Prerequisites, the dev container, building
Architecture	How the pieces fit, and where a change belongs
Protocol	The CC2 MQTT protocol, its quirks, zone detection, limits
Security	What an unauthenticated request can reach, and secrets
Gates	What the checks prove, and what they do not
Testing	How the suites are organised
Deployment	Why a merged commit is not a deployed one
Dependencies	What is pinned, and why
Lessons	Things that cost a day and should not cost another

Supported printers

Elegoo Centauri Carbon 2, and other printers speaking the same CC2 protocol. Resin printers (Mars, Saturn) use SDCP over WebSocket and are not supported.

Credits

• gcode-preview: Three.js toolpath rendering
• elegoo-link: Elegoo's official C++ SDK
• elegoo-homeassistant: CC2 protocol documentation
• Fluidd: UI inspiration
• mqtt.js: MQTT client

Forked from runnane/elegoo-web.

License

MIT. See LICENSE, which carries both the upstream author's copyright and this fork's.