What it is
jevrs is an async Rust client for TypeSafe AI's Jev (System One) API, giving Rust developers typed question sets and answers, a runtime builder, configurable retries, and native or WASI transports over a portable sans-I/O core.
How it uses Jev
Users derive Options, Levels, and Questions on structs to define Choice, Score, and Noul questions. Calling client.ask(&state) sends the state plus typed questions to Jev and returns typed answers; code reads probabilities via fields like is_urgent.p, department.pick, and frustration.expected().
Primitives:choicescorenoul
Technique worth stealing
Derive macros turn Rust enums and structs into typed Jev question sets and answers.
Try it
Set TYPESAFE_API_KEY and install with cargo add jevrs tokio --features tokio/macros,tokio/rt-multi-thread.
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-centricyes0.92
- Shows a System One patternno0.30
- Handles uncertaintyno0.05
- Measuredno0.04
- Runnableyes0.94
- Worth recommendingunclear0.44
- Model replicano0.03
- Problem scopescore on a 0–2 scale1.00
- About Jevyes0.99
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 21 Sept 2026.