Decision Warehouse
Every decision persisted. Zero hot-path overhead.
The decision warehouse captures every execution asynchronously — the caller gets the response as soon as the engine returns, the write happens in the background. KPI dashboards, champion/challenger analysis, and regulatory replay audits all run against the warehouse without touching the live execution path.
Async writer architecture
A dedicated in-process ring buffer drains to PostgreSQL on a separate writer pool — the execution thread pool is never blocked by I/O.
Zero hot-path latency
The caller receives the response as soon as the engine returns. Warehouse persistence happens in background — it does not add milliseconds to the decision round-trip.
No decisions lost on crash
The ring buffer is flushed to a WAL-replayed write-ahead log before the process exits. No decisions are silently dropped during an unclean shutdown.
Writer health is observable
GET /api/health/engine reports warehouse.writer_lag_ms and warehouse.queue_depth. High-water alerts are available for SRE pager integrations.
KPI dashboards
| Metric | Window |
|---|---|
| Decisions executed | 1 h / 24 h / 30 d |
| Mean & p99 latency | 1 h rolling |
| Error rate (ENGINE_BUDGET_EXCEEDED, etc.) | 24 h |
| Budget spend distribution | Per ruleset version |
| Champion/challenger variant split | Per experiment |
| Writer lag & queue depth | Live (health endpoint) |
Regulatory replay audits
Content hash proves which logic ran — not just which version
Every execute response includes content_hash in the envelope. The warehouse stores the hash alongside the input payload, execution trace, steps spent, and verdict. When a regulator asks "what decision was made for applicant X on date Y, and why?", the replay reconstructs the full trace from the warehouse — and the content hash proves the exact bytecode that produced it. A version number alone cannot, because versions can be rebuilt.
Decision warehouse is included on every plan
No add-on, no separate license. Start a trial to explore KPI dashboards and replay audits.