LibreDB Studiolibredb.orglibredb.org ONLINE • PostgreSQLWhy you can trust a pre-alpha engine: a CRC-32 checksummed, fsync-before-commit write-ahead log, crash recovery proven by deterministic simulation testing, 100% core line coverage — plus an honest list of what it deliberately is NOT yet.
SELECT guarantee, mechanism FROM reliability ORDER BY guarantee;Readable does not mean toy. We earn trust through tests, not line counts.
A transaction that returns has been written to a length-framed, CRC-32 checksummed log and fsync-dbefore the commit becomes visible. A crash can only ever damage the last, un-fsync-d record — which recovery detects and truncates, leaving a valid committed prefix.
The crash/recovery path is proven by running the real engine against a seeded in-memory filesystem that tears, corrupts, and crashes the log on command — then checking that recovery is always a valid committed prefix. The FoundationDB-style approach that keeps the durability claims honest.
These limits are deliberate v1 scope, not hidden gaps. LibreDB's strength comes from what it refuses.
| You need… | Why not yet |
|---|---|
| Production at scale | It is pre-alpha; today's beachhead is test/dev. |
| Secondary indexes / planner | Queries are O(n) scans by design in v1 (on the roadmap). |
| Concurrent / networked access | It is embedded and single-process — no replication or client/server. |
| SQL wire compatibility | No SQL text, no existing-driver ecosystem — a relational view, not a SQL engine. |
LibreDB is early (0.0.x). The architecture is in place and every line of the core is tested, but the API may still change and it is not yet meant for production data. Star it, follow along, and help shape it.