What it is
A Ruby gem that wraps Jev, TypeSafe's System One model, letting Ruby and Rails developers ask natural-language questions about application state and receive typed, probabilistic answers. Zero runtime dependencies.
How it uses Jev
Jev evaluates a state Hash against typed questions (Noul, Choice, Score) and returns calibrated probabilities. In code, Typesafe::Jev.evaluate returns a Response whose answers expose #noul, #choice, #probabilities, #score, #legend, and #confidence for programmatic decisions.
Primitives:choicescorenoul
Technique worth stealing
Typed question value objects validated at construction, so bad questions raise ArgumentError before any HTTP call.
Try it
gem install typesafe-jev, then call Typesafe::Jev.evaluate with state and questions.
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-centricyes0.86
- Shows a System One patternno0.13
- Handles uncertaintyno0.05
- Measuredno0.04
- Runnableyes0.98
- Worth recommendingno0.26
- Model replicano0.03
- Problem scopescore on a 0–2 scale1.06
- About Jevyes0.98
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 20 Sept 2026.