Observed arrival · 2026-09-22

Jev 101: A Field Manual for Software Decisions

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Editorial interest 82/100 Selection signal · not a rating of the site

An unofficial guide to TypeSafe’s System One / Jev, with foundations, recipes, ecosystem notes, and 55 decision-oriented use cases.

Landing page captured for the 2026-09-22 issue.

For: Developers evaluating typed decision systems
Worth noticing: The catalog contains 55 use-case outlines, including agent harness supervision and pre-commit change gates.

Field notes

The manual frames Jev as a typed decision layer: code retains control flow and side effects, while Jev handles narrower semantic judgments. Its catalog gives those primitives operational shapes, including allow/ask/deny gates, completion checks, skill selection, and staged code-review routing. The homepage labels the material unofficial and staging-only, so its examples are best read as a working field guide rather than authoritative product documentation.

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