Skip to content
System One

open-jev: one-pass option scoring with local models

Independent reimplementation inspired by jevlike that scores pre-written options in one batched forward pass by log-probability over a local Gemma 3 4B, shipping an HTTP server, CLI and a TypeSafe System One API implementation.

openjev playing Doom in the terminal: the model ranks the action menu each step
Image from github.com

daseinlabs/open-jev on GitHub

Stars
107
Forks
21
Language
Python
License
MIT
Last push
24 Sep 2026

Read from GitHub on . Counts change daily.

How it uses Jev

    @app.post("/v1/systemone", response_model=SystemOneResponse, dependencies=[Depends(_auth)])
    def systemone(req: SystemOneRequest) -> SystemOneResponse:
        """TypeSafe System One contract: state + typed questions -> typed answers (docs.typesafe.ai)."""
        scorer: OptionScorer = state.get("scorer")
        if scorer is None:
            raise HTTPException(503, "model still loading")
        try:
            return system_one(scorer, req, model_name=req.model or model_name)
        except ValueError as e:
            raise HTTPException(400, str(e))

    return app


def serve(host: str, port: int, model_path: str | None, batch_size: int, backend: str = "auto", device: str = "auto") -> None:

View in openjev/server.py

Open on GitHub

More like this

Use cases this is tagged with