Jev by TypeSafe AI: System One Models & Open-Source Alternatives
Curated by @tripp
Updated Sep 23, 2026
Learn Jev, TypeSafe AI's System One model, plus its open-source alternatives Laya and Von. This hands-on course covers the /v1/systemone API, the Choice, Score and Noul questions, confidence routing, TypeSafe's cookbooks, calibration (ECE), and CEO Diogo Almeida's "Prod, not God" thesis. You finish by building a triage pipeline that runs on either the hosted or a self-hosted backend.
Models used
Models the creator uses in this course — chat, study guides, flashcards, ingest. Updated when the listing is republished.
Syllabus
Folder tree from your library — expand modules to see lessons.
View full syllabusChangelog
- v1.02026-09-24
The course is complete. Module 05 adds a decision guide comparing Jev, Laya, Von and LLMs with structured outputs, with a cost/latency calculator and hybrid architectures, and a 60-minute capstone: a swappable ticket-triage pipeline with a mock evaluation harness. This release also fixes the syllabus practice prompt and the Laya server citation.
- v0.32026-09-23
Added Module 04, on open-source alternatives. The Laya lesson covers its architecture, how to read its calibration tables, its benchmarks against Jev, its first-party laya-serve /v1/systemone server, and a local demo. The Von lesson covers the protocol clone and includes a contract checker. The syllabus now lists recommended prerequisites from the public AI Engineering and RAG courses.
- v0.22026-09-23
Added Module 03: "Prod, not God". It covers CEO Diogo Almeida's Latent Space episode, with a chapter map, RLCD vs RLHF/RLVR, the refusals debate, traction claims, and a critical read of his claims against the launch materials. The syllabus prerequisites are now self-contained.
- v0.12026-09-23
First release: syllabus, Foundations (System One models and calibration) and Module 02, Jev in practice (API, the three question types, confidence routing, cookbooks and known limits). The CEO, open-source and capstone modules are coming next.
Attribution
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