Braintrust is an eval platform with a prompt playground and dataset management. It's built for evals before deploy, not governance after — no re-execution of production incidents, no policy enforcement, no signed audit trail.
| Capability | Braintrust | Runback | Note |
|---|---|---|---|
| Eval runner and dataset management | ✓ | ✓ | |
| Prompt playground and scoring | ✓ | ✓ | Includes pairwise (head-to-head) LLM-judge comparison with human calibration feedback |
| Human review UI | ✓ | ✗ | Braintrust speciality |
| Re-execute a production incident step-by-step | ✗ | ✓ | Braintrust replays eval DATASETS, not a specific captured production run — Runback bisects a live incident in log₂ tries |
| Live policy enforcement — block before it runs | ✗ | ✓ | Runback decides each tool call server-side, from its TypeScript and Python SDKs (not yet Go or an MCP proxy), against the policy version assigned to the agent; each assignment fails closed or open during an outage (closed by default for agents declared critical, once the SDK has fetched its policy bundle), and decisions are recorded and sealed — those the SDK makes on its own once Runback answers again |
| Golden corpus auto-mined from production failures | partial | ✓ | One-click promote-to-dataset plus auto-clustering of production traces — a manual promote step, not Runback's unattended mining |
| Signed, tamper-evident audit export | ✗ | ✓ | Enterprise audit logs record admin actions and are retained indefinitely; Braintrust's own guidance leaves immutability to WORM settings on the customer's storage bucket, and S3 export is a project-data export. We found no documented signature or hash chain — which is what lets a third party verify a record without trusting the vendor's storage |
| Regulatory mappings (EU AI Act · CPS 230 · NIST) | ✗ | ✓ |
It's built for evals before deploy, not governance after — no re-execution of production incidents, no policy enforcement, no signed audit trail. Most teams use both — Braintrust for what it's already good at, Runback for deterministic incident replay and the signed record.
Source: Braintrust's public documentation, https://www.braintrust.dev/docs, read 15 September 2026. Products change: report an error to legal@runback.dev and we will correct it. Names and trade marks belong to their owners; Runback is not affiliated with, endorsed or sponsored by any of them.
No signup. Walk the scripted failing demo run step by step and see what the model was given.