Open-source alternative
Replace MongoDB Atlas with FerretDB + Postgres
The best open-source alternative to MongoDB Atlas is FerretDB or PocketBase, self-hosted on Railway. Mongo-compatible documents on Postgres. FerretDB is Apache-2.0. MongoDB Community is SSPL — not OSI open source — so it is not the path.
Estimated save $2,400 a year.
Open the stackStart on Railway
How MongoDB Atlas compares
| MongoDB Atlas | FerretDB + Postgres | |
|---|---|---|
| Pricing model | Hosted subscription | Open-source or fair-code license; you pay the host |
| Hosting | Vendor cloud | Self-hosted on Railway or any VPS |
| Rough monthly cost | Public list price not verified this run | Hosting only — no SaaS seat meter in this repo |
- FerretDB
Apache-2.0 MongoDB-compatible proxy on Postgres
- PocketBase
Embedded SQLite app database if you do not need Mongo
FAQ
- Is it free?
- The FerretDB + Postgres licenses are open source or fair-code. You still pay hosting (Railway or any VPS) and any APIs the stack calls. There is no MongoDB Atlas seat or task bill on this path.
- Can I migrate from MongoDB Atlas?
- Yes. Start with the workflows or data you actually use, then cut over. The FerretDB + Postgres stack page has the agent prompt and the cost table; most teams rebuild the slice that matters and leave old MongoDB Atlas links until they expire.
- How do I deploy it?
- Open the FerretDB + Postgres stack, copy the agent prompt, and deploy on Railway (one service, PORT, and a volume when the app needs disk). Placeholder: FerretDB + the project's Postgres/DocumentDB image, data on a volume. Apps that do not need Mongo talk should use /stacks/go-pocketbase-htmx instead.
- What does this replace?
- MongoDB Atlas. The published small-team estimate on this stack is $2,400 a year.
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