Ex-OpenAI researcher launches Jev, a non-text "System One" decision model
TypeSafe AI, co-founded by ex-OpenAI researcher and InstructGPT co-author Diogo Almeida, emerged from two years of stealth to launch Jev, a proprietary "System One" model (early access) with a $40M seed round led by DCVC. Unlike LLMs, Jev generates no text: given a state and typed question, it returns schema-constrained answers—choices, scores, or typed numeric values with probability estimates and confidence scores—for direct consumption by other software.
Confirmed
- Response time of 70–500 ms; $0.042 per million input tokens, output free. Per Kuailiyu, up to 193x faster than large models, with per-decision cost around $0.0004.
- Founder Diogo Almeida claims he helped invent ChatGPT (AxSaucedo calls him co-inventor of RLHF) and spent two years researching an alternative training method.
- A Reddit explainer relayed by techtechnical says Jev uses RLCD (reinforcement learning from critique) for calibrated decisions; the "System One" name borrows from fast/slow thinking in psychology.
- Per Kuailiyu, 13% of teams paid within 24 hours of launch.
- One user (relayed by PrajwalTomar) tested Jev by hiding read counts of 468 tweets and asking it to predict them.
- Dhravya Shah (relayed by julianweisser and blaizedsouza) argues Jev is reshaping AI memory and context engineering, with benchmarks and use cases in computer use, browser use, and data labeling.
Unconfirmed
- The "193x faster" and "13% paying teams in 24 hours" figures come from secondary sources (Kuailiyu); the comparison baseline and methodology are not officially disclosed, and RLCD details come from community posts.
Why it matters
- Jev is positioned as a new primitive beyond LLMs: it cannot write essays, explain itself, or hallucinate much, making it suited for massive volumes of fast, cheap, calibrated bounded decisions inside agent runs (hardimanjames notes agents spend most time on small decisions, not "reasoning"), rather than conversation.
- Authors like danielmac8 argue its speed and pricing make it a judgment component that other systems can call at scale—an inverse exploration of the text-centric AI paradigm.
2026-09-23 ~ 2026-09-25 · 12 related posts
- Episode 1: Independent researcher says Jev is no breakthrough: he open-sourced a similar non-autoregressive decision model a year earlier(2026-09-20, 6 posts)
- Episode 2: ianand's Thought Experiment: An AI World Built on the Encoder(2026-09-20, 9 posts)
- Episode 3: Ex-OpenAI Founder Says RLHF Is a Detour, Human-AI Collaboration Era Ending(2026-09-20, 3 posts)
- Episode 4: Ex-OpenAI researcher launches decision model Jev with bold speed claims(2026-09-21, 36 posts)
- Episode 5: Jev: A Decision-Only AI Model Returns Probabilistic Answers in 200ms(2026-09-21, 2 posts)
- Episode 6: Decision Model Jev Opens to All, Developers Compare Buzz to GPT-3.5 Launch Week(2026-09-21, 2 posts)
- Episode 7: Jev model shines in tool use, lags in reasoning and retrieval(2026-09-22, 2 posts)
- Episode 8: Jev Model Sparks Debate: A Dedicated Decision Layer Beyond LLMs(2026-09-23, 4 posts)
- Episode 9: Decision-Only Model Jev Goes Viral as a Cheaper DeepSeek-Style Threat(2026-09-23, 3 posts)
- Episode 10: Ex-OpenAI researcher launches Jev, a non-text "System One" decision model(2026-09-23, 12 posts)
- Episode 11: TypeSafe's Jev Decision Model Sees Fastest Adoption, Sparks Open-Source Agent Ecosystem(2026-09-24, 5 posts)
Primary sources
- Ex-OpenAI team launches Jev, a non-LLM model that outputs typed values with confidence scores, raises $40M — cephaloform ·
- Jev: TypeSafe's 70-500ms System One AI primitive costs $0.042 per million input tokens — daniel_mac8 ·
- Ex-OpenAI researcher launches System One Models: Jev makes typed decisions in 70-500ms — JeremyCMorgan ·
- TypeSafe unveils Jev, a schema-only model answering in 70-500ms with free output — FinanceYF5 · 2026-09-23
- [source] Jev: TypeSafe's 70-500ms System One AI primitive costs $0.042 per million input tokens — daniel_mac8 · 2026-09-23
- [source] Ex-OpenAI team launches Jev, a non-LLM model that outputs typed values with confidence scores, raises $40M — cephaloform · 2026-09-24
- Jev, a text-free 'System One' model from ex-OpenAI staff, hits 13% Vercel adoption in 24 hours — 快鲤鱼 · 2026-09-24
- Jev, built by a ChatGPT co-inventor, answers yes/no in 100ms for near-zero cost — PrajwalTomar_ · 2026-09-25
- TypeSafe AI's Jev makes calibrated decisions in 70-500ms with free output tokens — blaizedsouza · 2026-09-25
- How Jev, a new System 1 model, changes memory and context engineering — julianweisser · 2026-09-25
- Ex-OpenAI RLHF co-inventor launches Jev: 100x faster, hallucination-free structured-output model — AxSaucedo · 2026-09-25
- TypeSafe AI launches Jev, a 'System One' model for bounded decisions in agent runs — hardimanjames · 2026-09-25
- TypeSafe's Jev model explained: calibrated confidence, constrained outputs, 'zero hallucinations' — tech_technical · 2026-09-25
2 near-duplicate retellings: blaizedsouza · JeremyCMorgan