Lean 4
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Use cases with Lean 4
Dev & opsHacker News · saviorand
Have Claude Code build a full-stack app in Lean 4 that passes the official test suite
A developer built RealWorld, the reference full-stack app with official test suites, entirely in the proof language Lean 4. He says almost none of the code was written by hand: Claude Code wrote the app at his direction and also contributed fixes to six of the libraries it uses.
$17/moWeeksAdvanced