Lean 4.34.0 (2026-09-14)
Lean 4.34.0 (2026-09-14) is Lean 4.34.0 is out: 159 changes. Three kernel soundness vulnerabilities fixed, all requiring deliberately constructed inputs rather than ordinary code. 𝚋𝚟_𝚍𝚎𝚌𝚒𝚍. It is ranked #342 on the Dev Radar, in Languages & runtimes, first seen 4 days ago and shared in 1 post (7.6k views).
Lean 4.34.0 (2026-09-14) The Lean Language Reference Lean 4.34.0 (2026-09-14) 🔗 For this release, 159 changes landed. In addition to the 55 feature additions and 63 fixes listed below, there were 5 refactoring changes, 5 documentation improvements, 6 performance improvements, 2 improvements to the test suite, and 23 other changes. Highlights 🔗 Lean 4.34.0 focuses on the kernel: three soundness issues, found with AI adversarial testing, have been analyzed and fixed, and a series of additional defensive checks have been implemented for further reinforcement. In the automation side, bv_decide gets integrated with sym and grind interactive…
What people said about Lean 4.34.0 (2026-09-14) on X
Lean 4.34.0 is out: 159 changes. Three kernel soundness vulnerabilities fixed, all requiring deliberately constructed inputs rather than ordinary code. 𝚋𝚟_𝚍𝚎𝚌𝚒𝚍𝚎 is up to 6x faster. https://lean-lang.org/doc/reference/latest/releases/v4.34.0/ #LeanLang #LeanProver
— @leanprover, 4 days ago · 250 likes · see the post
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Lean 4.34.0 (2026-09-14) in numbers
- Rank on the Dev Radar: #342 of 1347
- Shared in 1 post by 1 account: @leanprover
- 7.6k views on those posts
- First seen 4 days ago, last shared 4 days ago
- Pricing seen by Jev: open source
- Market: Languages & runtimes
FAQ
What is Lean 4.34.0 (2026-09-14)?
Lean 4.34.0 is out: 159 changes. Three kernel soundness vulnerabilities fixed, all requiring deliberately constructed inputs rather than ordinary code. 𝚋𝚟_𝚍𝚎𝚌𝚒𝚍 It was first shared on X 4 days ago and is ranked #342 on the Dev Radar.
Is Lean 4.34.0 (2026-09-14) free?
It is open source.
Who shared Lean 4.34.0 (2026-09-14)?
1 account on X, including @leanprover, in 1 post totalling 7.6k views.
Every post is read and classified by Jev (TypeSafe): what it is, which market it belongs to, and whether the link is a real tool. 12.2k posts from 4.7k X accounts over the last 21 days, 1.3k tools, 12 markets. Collected every 5 minutes, fully re-ranked every hour — last update 2026-09-19 16:57 UTC. Full method.