{
  "id": 15334898,
  "title": "Lean Now Ships with Verified Kernels",
  "url": "https://urgent.news/2026/10/16/lean-now-ships-with-verified-kernels",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-10-16T06:16:13.000Z",
  "source": {
    "name": "Hacker News",
    "slug": "hacker-news",
    "url": "https://leodemoura.github.io/blog/2026-10-15-lean-now-ships-with-verified-kernels/"
  },
  "original_language": "en",
  "account": "Lean now includes verified kernels, enhancing its capabilities for rechecking software. The AI agent tool, lake check, simplifies this process by exporting developments and rechecking them with the official kernel, leanchecker, without additional baggage. This sandboxed operation ensures security. Four new kernels, nanoda, lean4lean, con-leche, and con-ron, are available. The con-leche kernel, the first written in Lean and proven consistent, offers a significant advantage by minimizing bugs from kernel implementation mistakes without compromising performance. In fact, it runs 0.69 times less instructions than the official kernel, checking a full Mathlib export in approximately 100 seconds with eight threads. To further reduce risks, con-ron was created by translating con-leche to Rust and verifying its refining checking algorithm with Aeneas, a Lean tool. The combination of con-leche and con-ron provides robust protection against unsoundness bugs. Additionally, the verification of lean4lean is nearing completion, adding another verified kernel to the distribution. Arthur Adjedj is developing a plan to renovate the kernels, with several proposals already submitted and under review. Future plans include simplifying the lake check command, enabling users to integrate their preferred kernels, and verifying parts of the compiler. The community is also working on scalable solutions for larger projects, such as Anthropic's FLT and the General Courtade–Kumar theorem repo. Until then, users are encouraged to test their projects using lake check --paranoid and report any discrepancies to contact@lean-fro.org.",
  "summary": null,
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}