FORMAL VERIFICATION

Anthropic says Claude worked largely autonomously for 11 days to formalize Fermat's Last Theorem in Lean. The developer lesson is less about one theorem and more about verified repo-scale research artifacts.

Mistral releases Leanstral 1.5, an Apache-2.0 licensed 119B parameter model (6B active) for Lean 4 theorem proving that saturates miniF2F and achieves SOTA on FATE benchmarks.