I built a clean-room Google Firebase alternative that keeps the official SDKs and cuts your bill to a ~$5 VPS: unlimited projects, no per-operation pricing.
Aruma is an open-source backend you host yourself. It speaks the same protocols as Firebase, so your app keeps the official Firebase SDKs (JS, Android, iOS, Flutter, Admin); you just point them at your own server instead of Google's. The SDKs run in normal production mode, not emulator mode.
What works today:
- Authentication
- Realtime Database
- Cloud Storage
- Cloud Firestore
It ships as a single Go binary on PostgreSQL, and you own your data.
Clean-room: Firebase's backend is closed source, so Aruma was built from public documentation and the observed behavior of the SDKs against real Firebase and the emulators. No Google server code.
Status: early, not production-ready yet. I'm working toward a stable release and an automatic tool to migrate data off Firebase. Next: push notifications and App Check, then Remote Config and Functions.
Feedback I want most: SDK compatibility gaps. If your app breaks against Aruma, please open an issue.
Repo: https://github.com/arumadev/aruma Docs: https://arumadev.github.io/aruma