September 2026 · 252 commits
Lean 4 hardens verification and supercharges arithmetic tactics
September brought sandboxed project checking, major `grind`/`Sym.simp` upgrades, and several runtime and elaboration performance wins.
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2026
← RecentAugust 2026 · 228 commits
Lean 4 hardens the kernel, expands VCGen, and speeds tactics
August brought soundness fixes, major VCGen/contract work, faster grind/bv_decide paths, and sturdier Lake/build tooling.
Read the issue →July 2026 · 303 commits
Lean 4 sharpens verification, tactics, and kernel safety
July brought major vcgen/grounding work, faster grind/cbv paths, and several kernel soundness fixes.
Read the issue →June 2026 · 221 commits
Lean4 ships major tactic, snapshot, and float-model upgrades
June brought faster incremental loading, a major VCGen overhaul, float modeling, and big do/grind/lint improvements.
Read the issue →May 2026 · 188 commits
Lean4 month of solver hardening, new tactics, and IO/runtime fixes
Major work on grind, mvcgen', and SymM plus Lake/CI and runtime safety improvements across the month.
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