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Jevcompat

Testable 48-requirement spec plus conformance suite, normalising proxy and fault-injecting mock for Jev-compatible System One API servers; against the eight most-starred open servers only two passed every MUST requirement.

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0
Language
Python
License
MIT
Published by
Community
Last verified
Oct 2026

About this project

About a hundred servers say they are "Jev-compatible". Nothing said what that means. Now something does. jevcompat is three things for the TypeSafe System One API (POST /v1/systemone, the API behind Jev): SPEC.md: a numbered, testable specification: 48 requirements, each with a level (MUST / SHOULD) and the official source it comes from. Where TypeSafe's docs, OpenAPI file and SDKs disagree (they do, in eight places), it says which wins and why.

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

Highlights

  • 48 numbered requirements with MUST/SHOULD levels, each citing TypeSafe's docs, OpenAPI file or SDKs; it rules on the eight places those sources disagree
  • Measured 2026-09-24: kev (5.8k stars) and decider (338) were conformant; six others broke clients, with option caps at 26, 50, 64 or 128
  • Confidence means five different things across servers; at a 0.9 threshold TypeSafe's formula auto-accepted 58% of 204 recorded answers, Laya's 30%
  • The mock ships 47 deliberate faults, and CI proves every check fails on its target fault without smearing failures to unrelated MUSTs
  • The proxy recomputes choice, score, legend and confidence and fixes 38 of the 47 faults, refusing 9 with a 502 rather than passing them through

Watch out

MIT license. The spec is a draft and unofficial; it judges the wire contract only, not answer accuracy or calibration, and TypeSafe's own API was not tested for terms reasons.

Questions about this entry

Short answers drawn from the linked project or page.

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