Open source Self-hostable freemium
In these stacks
LicenseMIT
PriceFree tier
UsageNo model cost
Price detailSelf-host free; cloud tier
Model supportmulti
Languagespython, typescript
GitHub stars30.4k
Last activity2026-07-03
VerifiedThu Jun 25 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
Verified byseed
An open-source platform for tracing, prompt management, and evaluation that you can self-host to keep traces private.
Strengths
- Open source and self-hostable
- Framework-agnostic via OpenTelemetry
Tradeoffs
- Self-hosting ClickHouse is operational work
- Eval features trail dedicated eval tools
What people say
What people who use Langfuse actually say, pulled from verified sources and ranked by what's new.
Langfuse is the most-used open-source LLM observability tool; self-hosting keeps sensitive traces off vendor servers.
For pure regression testing rather than tracing, pair Langfuse with a dedicated eval tool; tracing alone will not catch quality drift.
Covers
Self-hosting