FerretDB vs SurrealDB
Both are alternatives to MongoDB Atlas. Here's how they stack up — verified facts, no spin.
Also searched as SurrealDB vs FerretDB — same comparison, one verdict.
FerretDB
MongoDB's wire protocol, speaking to Postgres underneath.
FerretDB implements the MongoDB wire protocol on top of Postgres, so an existing application keeps its drivers, its queries and its code while the data lives in an open relational database under a licence nobody will change. Apache-2.0, around 11k stars. It is the most surgical exit in this comparison: for the common case of a team using MongoDB as a straightforward document store, it is close to a drop-in. Compatibility is good rather than total — the exotic aggregation stages and MongoDB-specific features are where it stops.
SurrealDB
Documents, graph and relational in one engine — but check the licence.
SurrealDB is a Rust multi-model database combining document, graph and relational access through a single SQL-like language, with real-time queries and permissions built in. It is genuinely interesting engineering and around 32.8k stars. One correction that matters and that most listings get wrong: the core is licensed under the Business Source License 1.1, not an open-source licence. BSL restricts offering it as a competing service and converts to Apache-2.0 after a set period. For internal use that is usually fine; for anyone building a product on top, read it first.
Side by side
| FerretDB | SurrealDB | |
|---|---|---|
| Sovereignty Score | 95 | 68 |
| Open source | Yes | No |
| Self-hostable | Yes | Yes |
| Local-first | Yes | Yes |
| License | Apache-2.0 | BSL 1.1 (source-available, converts to Apache-2.0 over time) |
| Pricing | Free and open source. You run it alongside your own Postgres. | Free to self-host under BSL terms. Managed cloud is paid. |
FerretDB edges it on the Sovereignty Score, but the right pick depends on the trade-offs below.
FerretDB
Strengths
- +Existing MongoDB drivers and queries keep working — minimal code change
- +Apache-2.0, with data resting in Postgres
- +Sidesteps the SSPL question entirely
- +Lets you consolidate onto one database engine
Trade-offs
- −Compatibility is good but not complete — test your aggregations
- −Extra layer between application and storage
- −Younger project with a smaller community
- −Not faster than MongoDB; this is about licence and consolidation
SurrealDB
Strengths
- +Document, graph and relational in a single engine — genuinely rare
- +Real-time queries and row-level permissions built in
- +Rust, fast, and can embed directly in an application
- +Converts to Apache-2.0 on a published schedule
Trade-offs
- −BSL 1.1 is NOT open source, despite how it is usually listed
- −Young relative to Postgres or MongoDB
- −Smaller ecosystem and fewer battle-tested deployments
- −Multi-model flexibility is also more ways to model something badly
More MongoDB Atlas head-to-heads
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Facts verified 2026-08-07. Licenses and pricing change — spotted something out of date? That's a correction we want.