Open· Last updated 2026-09-21

Jev reference architecture

A reference architecture here is an unofficial box diagram in words: clients → your API → questions module → one TypeSafe door → traces → action / HITL. It is not TypeSafe’s unpublished internals.

Independent. docs.typesafe.ai. No keys.

Independent angle (cover, do not clone)

Win delta (architecture-known-unknowns): reference boxes you can implement; no fake internal diagrams.

Boxes

1. Clients — product apps; they see enums, not raw Nouls.
2. Decision service — auth, timeouts, idempotency, door adapter.
3. Questions module — git-versioned instructions/criteria/floors.
4. Door — first-party HTTP/SDK or a documented gateway (matrix).
5. Trace store — model, usage, probabilities, action, question SHA.
6. HITL — review UI.
7. Eval job — gold JSONL, pinned model.

Non-boxes (do not add)

• A fictional TypeSafe orchestrator
• A local Jev binary
• A “rationale generator” calling itself Jev

Failure domains

• Door outage — fail to HITL or deterministic default; do not infinite-retry 529.
• Bad questions deploy — 422 spike; revert the questions SHA, not “the model.”
• Alias move — response.model changes; floors may be wrong.
• PII leak — too much state; fix the filter, not the vendor first.

None of these require knowing unpublished model architecture.

What this page does not claim

• Not an official reference architecture from TypeSafe.

FAQ

Where does LangChain sit? Optional harness in the client or service. See LangChain harness.

Multi-region? Your service + vendor residency. Ask TypeSafe; we will not invent regions.

Disclaimer

This is an independent unofficial site and is not affiliated with TypeSafe AI; official documentation is available at https://docs.typesafe.ai. Never treat jev.pro as TypeSafe official documentation. We do not sell, issue, or proxy API keys.

Open-cluster pages are independent field-guide notes. Replicas and third-party interfaces mentioned anywhere on jev.pro are not Jev and not endorsed. Hub: Open. Siblings: architecture patterns, implementation checklist, for platform teams. Canonical: https://docs.typesafe.ai.