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Jev Labs

Consensus kernel that wraps Jev as a probabilistic oracle: five paraphrased questions, a stability gate set from the measured noise floor and a 3-of-5 quorum, with TLA+ specs, an AsyncAPI contract and Rust tests generated and gated from them.

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2
Language
Python
License
MIT
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Community
Author
copyleftdev
Last verified
Oct 2026

copyleftdev/jev-labs

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Never confidently wrong: a TLA+-verified consensus kernel around TypeSafe's Jev, run through 1,680 chaos-tested pharmacy decisions with zero wrong verdicts. Film, code, and every captured call.

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Updated Sep 2026

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About this project

Never confidently wrong. A consensus kernel around a probabilistic oracle, tested the way you would test a database: model-checked in TLA+, contract-generated into Rust, and run through 1,680 simulated pharmacy decisions under seeded chaos against the live Jev API. Watch the 4-minute film — every number on screen is read from story/storydata.json, which is built from the captured rounds in this repo.

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

Highlights

  • Zero wrong verdicts across 1,080 golden rounds, bounding the violation rate below 0.28% at 95% confidence, with 46 escalations under severe chaos.
  • Noise floors measured over 1,490 hash-verified calls: 0.042 identical, 0.059 reordered, 0.073 across paraphrases — and the gate uses them.
  • The quorum bound was derived by a 24-configuration TLC sweep rather than assumed; two configs are kept as deliberate failures.
  • Every round replays from its seed; the run caught a mislabelled case and a fail-fast path that voided 71% of rounds under severe chaos.

Watch out

Every number here comes from synthetic pharmacy scenarios the author wrote to have unambiguous answers, so the claims are about the protocol under chaos and not about whether Jev is competent on pharmaceuticals — the README says exactly that. The safety argument rests on zero wrong verdicts in golden rounds, and the author is explicit that this bounds the violation rate rather than proving it is zero; on an underdetermined record the kernel decided 34 times out of 120, because the stability gate filters noise rather than checking answerability. Reproducing the chain needs a TypeSafe key, Java plus tla2tools.jar for TLC, Node for the AsyncAPI step and about three minutes, and the noise floors were measured on one model version. 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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