{
  "name": "The Kernel Index",
  "description": "What formal mathematical libraries rest on: theorems depending on an unfinished proof, on the compiler rather than the kernel, and on an optional axiom. Measured by one program across two proof systems and six foundations.",
  "version": "2026-08-05",
  "sha256": "9d0bf4f36a423930fe01144235192fb4cb384487499ddda7c47c9a265e977dbb",
  "url": "https://f-keys.com/gonzalgo/kernel-index/",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "producedBy": {
    "software": "gonzalgo",
    "url": "https://pypi.org/project/gonzalgo/",
    "paper": "https://doi.org/10.5281/zenodo.21769846"
  },
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    "Lean 4": "4.32.1 with Mathlib",
    "Metamath": "set.mm, iset.mm, nf.mm, ql.mm, hol.mm"
  },
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    "optional_axiom",
    "optional_reach",
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    "axioms_used",
    "entry_points",
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    "amplification"
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      "label": "compiler-trusted"
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      "label": "optional axiom"
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