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Short, concrete writing on invariants, property-based testing, and keeping AI-written code honest.

What we do→
June 28, 2026 · Morgan · 4 min read

AI writes more of our code every week. Keel is the invariant layer that mines the guarantees your codebase depends on and enforces them on every pull request.

What is property-based testing?→
June 28, 2026 · Morgan · 6 min read

Example tests check the cases you thought of. Property-based testing states a rule that must hold for every input, then lets the computer hunt for the counterexample.

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