Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Maximus Gorog ba016b2130
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Phase 0: fork infrastructure
Add FORK_STRATEGY.md documenting:
- Purpose: HoTT-compatible kernel extensions (Path types without UIP,
  transport, HITs) for polytropos's meta-theory.
- Why kernel-level: library encodings via Quot leak UIP, incompatible
  with univalence. Mirrors Cubical Agda's precedent.
- Sync strategy: track upstream leanprover/lean4, merge (not rebase),
  preserve HoTT additions on conflict.
- Modification strategy: locality principle (new files under hott/
  + src/kernel/hott/ + src/Init/HoTT/); LEAN4-HTT: tag for modifications
  to upstream files; compile-time feature flag (LEAN_HOTT) gates HoTT.
- Patch-series organization for phased primitive additions.
- Forbidden moves: no UIP at kernel level, no Quot.sound dependency for
  HoTT reductions, no Classical.choice in HoTT primitives.

Add hott/ directory structure:
- hott/README.md describing the fork-specific directory's purpose.
- hott/design/ for architectural decisions per phase.
- hott/tests/ for HoTT-specific test suites.

No kernel modifications in this phase. Subsequent phases:
  Phase 1: Path + Refl + J primitives
  Phase 2: transport with computational behavior
  Phase 3: HIT support
  Phase 4: cubical primitives if needed

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-22 12:43:41 -06:00
.claude doc: add CLAUDE.md guidance on rebasing vs changing PR base (#13652) 2026-05-09 11:34:50 +00:00
.github chore: CI: fix stage2 release build (#13790) 2026-05-19 19:23:57 +00:00
.vscode chore: fixes from #13103 "enable separate codegen" (#13241) 2026-04-02 11:13:22 +00:00
doc chore: adjust dev-release preset (#13741) 2026-05-16 05:32:16 +00:00
hott Phase 0: fork infrastructure 2026-05-22 12:43:41 -06:00
images chore(CMakeLists.txt): move Lean logo to make sure we can test leanemacs without installing Lean 2015-01-31 17:38:49 -08:00
releases_drafts chore: remove stale release draft notes (#12518) 2026-02-17 19:56:23 +00:00
script chore: update release tooling and docs (#13631) 2026-05-04 15:33:36 +00:00
src fix: run beforeElaboration attributes on inductives (#13813) 2026-05-21 19:45:59 +00:00
stage0 chore: update stage0 2026-05-20 11:40:02 +00:00
tests fix: run beforeElaboration attributes on inductives (#13813) 2026-05-21 19:45:59 +00:00
.gitattributes chore: migrate more tests to new test suite (#12809) 2026-03-06 16:52:01 +00:00
.gitignore chore: update release tooling and docs (#13631) 2026-05-04 15:33:36 +00:00
.gitpod.Dockerfile chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.gitpod.yml chore: strip binaries only in release builds (#13208) 2026-03-31 17:18:43 +00:00
.ignore chore: ignore stage0/ (for rg etc.) 2022-03-18 15:28:20 +01:00
AGENTS.md chore: add AGENTS.md symlink to CLAUDE.md (#13461) 2026-04-18 06:48:05 +00:00
CMakeLists.txt chore: use the lean-llvm LLVM for benchmarking (#13634) 2026-05-05 14:26:08 +00:00
CMakePresets.json chore: adjust dev-release preset (#13741) 2026-05-16 05:32:16 +00:00
CODEOWNERS chore: make @hargoniX code owner of the compiler (#10732) 2025-10-10 04:43:38 +00:00
CONTRIBUTING.md chore: migrate pkg tests (#12889) 2026-03-11 18:55:46 +00:00
flake.lock chore: update to c++20 (#12117) 2026-02-11 01:17:40 +00:00
flake.nix chore: add aarch64-darwin to flake (#12915) 2026-03-18 15:55:34 +00:00
FORK_STRATEGY.md Phase 0: fork infrastructure 2026-05-22 12:43:41 -06:00
lean-toolchain chore: relative lean-toolchains (#12652) 2026-02-25 10:23:35 +00:00
LICENSE chore: remove LICENSE header that confused GitHub 2021-11-18 09:42:35 +01:00
LICENSES feat: bundle leantar with Lean (#12822) 2026-03-09 20:10:59 +00:00
README.md doc: update URLs that are currently pointing to redirects (#10397) 2025-09-17 15:50:07 +00:00
RELEASES.md chore: updates to release_checklist.md (#7817) 2025-04-04 03:45:36 +00:00

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