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CommunityPractices & Patterns97 starsVerified 2026-09-22

openjev

One-pass option scoring with a local Gemma 3 4B on Apple silicon via MLX: it prefills the context once, expands that KV cache across the option batch, and scores every option in a single padded forward pass with no decoding.

Category
Practices & Patterns
Published by
Community
Author
daseinlabs
Added
2026-09-22
Tagscommunitypythonopen-modelscalibrationdemo

Highlights

  • Implements the TypeSafe System One contract at POST /v1/systemone, scoring option names, level numbers, or yes/no in one prefix-shared pass per question.
  • The server loads the model once and answers scoring requests in about 90 ms each, running natively on macOS with Metal.
  • Supports choice (up to 255 options), score (ordered levels), and noul questions, returning probabilities and a confidence approximation.
  • make check verifies the cached batched scoring path against naive re-encoding, and make bench measures latency.
  • Includes a terminal Doom demo where the server picks every action, plus jevlike-style JSONL evaluation with top-1 and top-3 accuracy.

Quickstart

bash
make setup
make serve
.venv/bin/openjev score --context "The capital of France is" \
    --option " Paris" --option " Berlin" --option " Lyon"

Watch out

No license file, so reuse terms are unclear; needs an Apple silicon Mac (there is no container path because Linux cannot reach the Apple GPU) and a gated google/gemma-3-4b-it download requiring Hugging Face login.

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