Observed arrival · 2026-10-20
Lema: contracts and proofs for code
Lema is an experimental programming language whose documentation describes humans writing contracts and coding agents supplying implementations and proofs, checked by a Lean kernel.
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- Engineers reviewing agent-written code
- Worth noticing
- The documented kernel replay uses Lean 4.34.1 and explicitly excludes runtime, memory, compiler, operating-system, and network behavior from what is proved.
Field notes
The sorting walkthrough separates two properties that a simple example can miss: ordered output and preservation of every input element, including duplicates. The documentation also lists standard-library examples for SHA-256, HMAC, and AWS Signature Version 4, while distinguishing kernel-checked claims from behavior it treats as tested or assumed.
Observed signals
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○OpenPublic substance visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
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