Open source Self-hostable free
In these stacks
LicenseElastic-2.0
PriceFree tier
UsageNo model cost
Model supportmulti
Languagespython, typescript
GitHub stars10.4k
Last activity2026-07-04
VerifiedThu Jun 25 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
Verified byseed
An open-source observability and eval tool built on OpenTelemetry, with strong tracing and LLM-as-a-judge evals.
Strengths
- Open source with OTel foundations
- Good LLM-as-a-judge evals built in
Tradeoffs
- Elastic license restricts some hosted offerings
- Enterprise features in the paid Arize cloud