Braintrust
ObservabilityProprietary · Proprietary (platform); autoevals is MIT★ 1,044（2026-10-04）Managed only
Eval-first AI observability platform with an open-source autoevals library.
Braintrust is an eval-first AI observability platform whose own storage engine Brainstore is proprietary and written in Rust; its open-source autoevals library is MIT-licensed, and the company raised an $80M Series B in February 2026 at a reported ~$800M valuation.
Caveat: Self-hosting availability is unclear: sources conflict on whether it is a general option or enterprise-only.
Key facts
| Category | Observability |
|---|---|
| License | Proprietary (platform); autoevals is MIT |
| Language | TypeScript (SDK) |
| Self-hosted | No |
| GitHub stars | 1,044 (2026-10-04) |
| Last push | 2026-10-02 |
| Last verified | 2026-10-04 |
| Repository | https://github.com/braintrustdata/autoevals |
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