Evaluation-first platform with proxy layer vs proxy-first platform with built-in tracing. Different starting points, overlapping features.
| Feature | Stockyard | Braintrust |
|---|---|---|
| Architecture | Single Go binary, self-hosted | Managed SaaS platform |
| Primary focus | LLM proxy with tracing & security | LLM evaluation with proxy features |
| Self-hosted option | ✓ Default (single binary) | Cloud-only |
| External database | None (embedded SQLite) | Managed by Braintrust |
| LLM providers | 40+ built-in | 20+ via proxy |
| OpenAI-compatible | ✓ Native | ✓ Compatible |
| Evaluation / evals | Via Tack Room experiments | ✓ Core feature |
| Request tracing | ✓ Built-in (Lookout) | ✓ Built-in |
| Cost tracking | ✓ Per-request | ✓ Per-request |
| Prompt management | ✓ Tack Room | ✓ Built-in |
| Audit trail | ✓ Hash-chained | Logging |
| Pricing | Free tier, paid from $0.99/mo per tool | Free tier, usage-based pricing |
Based on publicly available documentation as of March 2026.
Braintrust started as an evaluation platform and added a proxy layer. Stockyard started as a proxy and added evaluation through Tack Room experiments. Both now cover routing, tracing, and prompt management, but their strengths reflect their origins.
If your primary need is rigorous eval workflows with scoring, datasets, and experiment tracking, Braintrust has deeper tooling there. If your primary need is a self-hosted proxy with operational features like cost control, caching, and audit trails, Stockyard covers more ground.
Braintrust is cloud-only. Your prompts and completions flow through their infrastructure. Stockyard runs on your servers. The proxy, traces, and audit data stay on your network.
For teams with data residency requirements, regulated industries, or a preference for infrastructure they control, Stockyard is the only option of the two that works. Braintrust is the better choice if you want zero infrastructure management and can accept SaaS data handling.
Choose Braintrust if LLM evaluation is your primary workflow, you want managed infrastructure, and you need deep experiment tracking with scoring pipelines.
Choose Stockyard if you need a self-hosted proxy with zero dependencies, built-in security features, and you want evaluation capabilities alongside your proxy rather than as a separate service.