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Open Jev — kyegomez

Unofficial PyTorch reconstruction of the ideas behind Jev, encoding state once and answering each question through small typed readout heads in a single parallel pass.

Stars
99
Language
Python
License
APACHE-2.0
Published by
Community
Author
kyegomez
Last verified
Oct 2026

This is one of several Jev listings for the same project. The canonical entry is Open Jev — nico-martin.

About this project

An open-source, from-first-principles reconstruction of the ideas behind TypeSafe AI's Jev, written in PyTorch. Jev is presented as a system one model: unstructured program state goes in, typed probabilistic decisions come out. Instead of generating text one token at a time, this implementation encodes the state once and answers every question through small typed readout heads.

Quoted from the project's README. Read the full README.

Highlights

  • Implements Noul probability, Choice over runtime-supplied options, and Score with ordinal thresholds plus expectation.
  • Questions are isolated in the batch dimension and cross-attend to a shared cacheable state representation.
  • Training loss accepts soft probability targets with calibration and consistency terms instead of one-hot labels.
  • Ships with a deterministic hash tokenizer adequate for running the architecture but not for training a useful model.

Watch out

Weights are random with no trained checkpoints, so outputs are illustrative and calibration must be remeasured before unattended use. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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From the Jev guides

Original write-ups on what this entry is for.

A game tick is a state plus a legal action list. How Clash Royale, Minecraft, and the earlier Mario, Pokémon, StarCraft, and drone loops ask Jev one step at a time.
Jev Demos & Experiments#gaming#agents#control
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