Drew T
fe399b4550
tools/verify_worktree.py: check a commit out into its own git worktree, provision the
untracked build deps (cc1 from the COMMITTED tarball, checksum-verified against the
COMMITTED record; .venv + extracted/ symlinked; maspsx submodule at the expected pin),
run make extract-all && check-all there, write .run/verify/<sha>.json with verdict +
toolchain provenance.
RESULTS
GREEN at HEAD: 213 passed / 0 failed, 86.6s wall.
NEGATIVE CONTROL PASSES: a throwaway commit splicing a deliberately corrupted body over
func_8014CBE8 went RED naming exactly ov_SC02_037 (212/1 of 213). The detector fires, so
its green means something (R35 — an unproven detector's green is not evidence).
TWO DESIGN CLAIMS CORRECTED BY CONTACT WITH REALITY
1. Sparse checkout (to save ~1GB of ghidra/) was proposed, and would have owed an R34
sparse-vs-full validation. Measured free space: 941 GB. Full checkout instead —
simpler AND strictly more trustworthy; the validation obligation disappears.
2. "A pristine checkout of exactly C's tracked content rebuilds byte-identical" is NOT
ACHIEVABLE here. Only 3 files under extracted/ are tracked; the 760MB of ROM payloads
are gitignored, so a pristine checkout extracts NOTHING (first honest run: 212/212
FAIL). No commit in this repo is self-sufficient, by design. The honest claim is
"the commit's TRACKED SOURCE, built against a supplied extraction" — corrected in the
docstring AND in the emitted `licenses` string, which is what actually gets quoted.
SCOPE, REFRAMED (Drew's challenge, and he was right)
I sold this partly on concurrency. At 86.6s, serializing R22 costs almost nothing, so the
concurrency argument is WEAK. What it actually buys is commit-completeness: the worktree's
src/ holds only committed content, so a source file someone forgot to `git add` fails BY
CONSTRUCTION — the documented "a clone of such a bank commit failed to build" class.
=> Run it at checkpoints and before pushing, NOT every batch. Plain in-tree check-all is
fine for routine verification.
=> The wave-vs-`make clean` blocker that started all this was already solved, more simply,
by tools/wave_snapshot.py. Neither the worktree nor path-parameterizing was needed for it.
=> STAGE 5 (verify coalescing / auto-bisect) IS CANCELLED: it existed to handle verify
lagging commits, which cannot happen at 87 seconds.
BFM-decomp
A matching decompilation of Brave Fencer Musashi (PlayStation, SLUS-00726, USA 1998) — the first public decompilation effort for this game.
What "matching" means
The goal is C source code that, compiled with the original-era toolchain (PsyQ 4.x / GCC 2.7.2-family + ASPSX via maspsx), produces a byte-for-byte identical SLUS_007.26 and, eventually, byte-identical overlay binaries. SHA1 checksums are the ground truth; "functionally equivalent" does not count.
No ROM content
This repository contains no game assets, no disassembly output, and no ROM-derived data — only source code, build configuration, symbol names/addresses, hashes, and documentation. To build or contribute you must provide your own dump of the game disc (4-track BIN/CUE, redump layout). See .gitignore for the firewall.
Project status
Latest (Phase 19, 2026-06-20): the project builds 136 binaries byte-identical from a clean tree (the EXE + the resident engine + all 134 location overlays);
make check-all→ 136/136. Fleet byte-identical-from-source is 58.0% (function-instance-weighted; see the PhaseEnds for the byte-weighted ~30% figure and what it includes). Shared engine functions are matched once inov_SC01_077and propagated ×134 viatools/dedup_propagate.py. (The narrative below is Phase-11/12-era; a full refresh is part of the public-flip prep.)
Gen1 (foundation) complete — the matching pipeline is proven end-to-end. make extract && make build && make check rebuilds SLUS_007.26 byte-for-byte identical (SHA1 143dbb89…) from C + assembly, reproducibly across many sessions.
- Compiler pinned by evidence:
gcc-2.7.2-psx -O2 -G0 -mips1 -mcpu=3000+maspsx --aspsx-version=2.56 --expand-div. - 52 functions hand-matched to byte-identical machine code — including the LZSS streaming decompressor — with a decomp-permuter + matching-cookbook "flywheel" to accelerate the next.
- 959 PsyQ SDK functions linked byte-identical (libcd, libgs, libgte, libspu/libsnd, libgpu, libc2, libmcrd, libapi/libcard, libetc) straight from the real PsyQ 4.0 libraries instead of re-decompiling them — bringing byte-identical-from-source coverage of the EXE to ~50%.
- File-loader / overlay system reverse-engineered, with the resident engine blob + location overlays' load addresses proven byte-identical against a live PCSX-Redux RAM dump.
About half the EXE is still INCLUDE_ASM stubs (correct bytes, not yet C), and the bulk of the game lives in compressed overlays inside the .CD archives — Gen2 (overlays & engine at scale) is underway:
- The build toolchain is binary-agnostic (one parameterized pipeline builds any binary), and the always-resident engine blob rebuilds byte-for-byte from source (SHA1
8e17e02f…) — the second binary reconstructed exactly, after the EXE — and is now 86% hand-matched C (123 / 146 functions, up from 0): its scripting turned out to be compiled-MIPS state/mode dispatch, not a bytecode VM, and the save-file + sound (SQV) formats are documented. The harvest used a reusable swarm-of-agents + bit-for-bit byte-gate method (a wrong match can't be accepted) —tools/harvest_verify.py+tools/match_one.py, which carry straight into the overlay phase. - A cross-binary deduplication pipeline is live: a Ghidra-free signer fingerprints all 134 location overlays, and the report finds ~9,000 byte-identical function groups shared across binaries (~28 MB of collapsible code) — a single engine function is byte-identical in all 134 overlays. This is "one match unlocks many": each engine match will be auto-credited across the overlay fleet.
Current phase and detailed progress live in phase-ends/ (newest PhaseEnd_*.md = current state); methodology, rules, and the full roadmap are in PROJECT_CONTEXT.md; environment setup in docs/SETUP.md.
This project is developed primarily by Claude Code driving Ghidra through an MCP server; see CLAUDE.md.
License
Private repository for now. AGPL-3.0 is planned at public release, modeled on sotn-decomp. tools/brave-CUE/ is CUE's BRAVE extractor (GPL, source included) and retains its own license.