Ex-OpenAI researcher launches System One Models: Jev makes typed decisions in 70-500ms

JeremyCMorgan · x · 2026-09-25

TypeSafe AI, founded by ex-OpenAI researcher Diogo Almeida, unveils "System One Models" — a new class of models that skip text generation and output typed, probabilistic decisions software can consume directly. The first model, Jev, is in early access: it claims frontier-level intelligence on decision tasks at 70-500ms latency, two orders of magnitude faster and more efficient than LLMs, and hallucination-free since it only produces structured outputs. The stack includes a new architecture, a parallel sampler, and a training method called RLCD (Reinforcement Learning for Calibrated Decisions). The team discloses its eval caveats: reference answers are averages of two frontier LLMs and workflows were written in-house. Positioned as "a frontier-intelligence function call."

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