What it is
A community Scala 3 SDK for TypeSafe AI's Jev System One model, which answers typed questions about a state instead of generating text. It targets Scala developers who want routing, gating, ranking or guardrail decisions inside an application.
How it uses Jev
You build typed questions — noul, choice, score — over a state, then call ask or run. Jev returns probabilities, a distribution and a confidence, looked up with the question value itself. Every call returns an Either, and probabilities are typed so values outside [0, 1] fail decoding.
Primitives:noulchoicescore
Technique worth stealing
Answers are retrieved with the question value itself, so the answer type follows the question without casting.
Try it
Add the scala-jev-sdk dependency, create a client with an sttp backend, then call ask with a 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-centricyes0.96
- Shows a System One patternno0.17
- Handles uncertaintyno0.04
- Measuredno0.04
- Runnableyes0.97
- Worth recommendingunclear0.40
- Model replicano0.03
- Problem scopescore on a 0–2 scale1.00
- About Jevyes0.98
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 20 Sept 2026.