What it is
An open re-creation of Jev, TypeSafe's System One model, built on Qwen3.5-4B. It answers typed questions about a state (text or image) with calibrated probabilities, for developers who need fast structured judgments instead of prose.
How it uses Jev
Jev is the model reflex re-creates. Given a state and typed questions (choice, score, noul), reflex returns calibrated probabilities in one forward pass, about 200 ms. Your code sets thresholds on those numbers, e.g. auto-route if above 90%.
Primitives:choicescorenoul
Technique worth stealing
Readout: lettered yes/no answer, Evidence / Criterion framing, averaging two distinct option orders.
Try it
git checkout stable && uv run reflex-serve --stable on a 16 GB CUDA GPU; or try the WebGPU demo.
Evidence
Each line is one question put to Jev about the README. ≥ 0.60 reads as yes, ≤ 0.40 as no; in between Jev is not making a call.
- Jev-centricyes0.84
- Shows a System One patternyes0.78
- Handles uncertaintyno0.06
- Measuredno0.09
- Runnableyes0.84
- Worth recommendingno0.38
- Model replicayes0.96
- Problem scopescore on a 0–2 scale0.91
- About Jevyes0.98
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 21 Sept 2026.