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 is open source (Apache-2.0) and SurrealDB is not (BSL 1.1 (source-available, converts to Apache-2.0 over time)) — so the real question is whether you want to own the managed databases stack or rent it.
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
10 points of comparison, every one read from a verified field. Green marks the side that wins a row outright. A dash means we do not hold that fact — never that it is zero.
| FerretDB | SurrealDB | |
|---|---|---|
| Sovereignty ScoreOur transparent 0–100 composite for data ownership and exit cost. | 95 | 68 |
| Open source | Yes | No |
| Self-hostable | Yes | Yes |
| Local-first data | 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. |
| RAM to run it wellThe figure that actually matters, not the vendor's minimum. | — | 4 GB |
| Realistic running costWhat the box costs each month if you run it yourself. | — | $18–40/mo for a single node |
| Setup timeHonest first-install estimate, not the marketing quickstart. | — | 1 hour |
| Ongoing maintenanceThe part nobody budgets for. | — | Moderate, and version churn is the real cost. |
FerretDB edges it on the Sovereignty Score, but the right pick depends on the trade-offs below.
Weighing both against staying on MongoDB Atlas? Is MongoDB Atlas free? What it actually costs →
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
Which one fits you
The trade-offs above, turned into a decision. Find the line that describes your team.
Choose FerretDB
if you want the source and the option to fork it, and existing MongoDB drivers and queries keep working — minimal code change.
Choose SurrealDB
if document, graph and relational in a single engine — genuinely rare.
Neither, yet
if both carry a real cost you should weigh first — compatibility is good but not complete — test your aggregations, and bSL 1.1 is NOT open source, despite how it is usually listed. If either of those is a dealbreaker for your team, the shortlist is wrong rather than the choice.
What it takes to run these yourself
Real requirements and honest running costs, not the vendor quickstart.
FerretDB vs SurrealDB — common questions
Is FerretDB a better fit than SurrealDB for managed databases?
It depends on what you are optimising for, and the honest split is this: FerretDB scores 95 to SurrealDB's 68 on data ownership and exit cost, so it is the safer choice if you care about being able to leave. SurrealDB earns its place on a different axis — document, graph and relational in a single engine — genuinely rare. Neither is a wrong answer for every team; the table above is the actual comparison.
What happens if we want to switch later?
FerretDB keeps its data local or in open formats, so leaving is an export rather than a negotiation. SurrealDB is still self-hostable, so the files stay on your server either way — but it is not local-first by design, so check what its export produces before you rely on it.
Can I self-host FerretDB or SurrealDB?
Both can be self-hosted. The difference is what it costs you in time rather than whether it is possible — see the setup and maintenance rows above.
Are FerretDB and SurrealDB both alternatives to MongoDB Atlas?
Yes — both appear in our MongoDB Atlas comparison, which is why they are worth putting side by side. People usually arrive here already having decided to move off MongoDB Atlas and now choosing between the two replacements, which is a narrower and much easier question.
More MongoDB Atlas head-to-heads
Related alternative guides
Facts verified 2026-08-07. Licenses and pricing change — spotted something out of date? That's a correction we want.