# memory of alessa: an in-progress Silent Hill 3 PS2 matching decompilation

> Decompiles the PS2 executable and 40 overlays of Silent Hill 3 (NTSC-U v1.02) into C for Metrowerks CodeWarrior, and works alongside on the Silent Hill 2 engine, whose debug symbols from a 2001 prototype supply original names for shared code. Builds link with generated assembly for unmatched functions and are checked by SHA-256 against committed hashes. The README calls the project early-stage; decomp.dev reports about 9% of Silent Hill 3 functions and 58% of Silent Hill 2 functions matched at the pinned commit.

- Type: Case study
- Targets: Game
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-10-19
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/dreamingmoths/memory-of-alessa>
- Primary source: <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/README.md>
- Catalog page: <https://awesomerea.org/resources/silent-hill-3-memory-of-alessa-decomp-case/>
- Record JSON: <https://awesomerea.org/resources/silent-hill-3-memory-of-alessa-decomp-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/silent-hill-3-memory-of-alessa-decomp-case/index.md)

## Requirements & limits

- Targets Silent Hill 3 NTSC-U v1.02 (SLUS_206.22) and the Silent Hill 2 engine from the 0.10 VW047-U1 prototype. Builds use assembly for unmatched functions; the project reports 718/8,002 and 2,530/4,371 functions matched respectively.
- Supply the Silent Hill 3 SLUS_206.22 executable and B0.MFA archive; the optional Silent Hill 2 build needs prototype SLUS_202.28 and its overlays.
- Hosts are x86-64 Linux, Apple Silicon macOS or Windows through WSL, with Python 3, wget and build tools. make downloads CodeWarrior PS2 3.0.3 for Silent Hill 3 or 2.4 for Silent Hill 2, wibo, PS2 binutils v0.10 and objdiff; it uses the mwccgap submodule.
- diff.sh compares the rebuilt executable and overlays with SHA-256 entries; outside CI a mismatch does not fail make. CI uses a private container image.
- Project code is MIT; the games and assets retain separate rights. Fifteen files carry Sony confidential notices, and the vsm trees contain disassembled VU microcode. The project prohibits LLM contributions from 2026-09-26.

## Primary sources

1. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/README.md>
2. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/docs/development.md>
3. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/docs/llm-policy.md>
4. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/Makefile>
5. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/silent-hill-3/Makefile>
6. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/silent-hill-2/Makefile>
7. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/tools/scripts/diff.sh>
8. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/silent-hill-3/config/SLUS_206.22/checksum.sha>
9. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/.github/workflows/build.yaml>
10. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/.gitmodules>
11. <https://github.com/dreamingmoths/memory-of-alessa/tree/28cb323c31d94518e475924302e14cd87d6963a8/include/sce>
12. <https://github.com/dreamingmoths/memory-of-alessa/tree/28cb323c31d94518e475924302e14cd87d6963a8/vsm>
13. <https://github.com/dreamingmoths/memory-of-alessa/blob/28cb323c31d94518e475924302e14cd87d6963a8/LICENSE>
14. <https://decomp.dev/dreamingmoths/memory-of-alessa>

## More in Games

- [meteor-decomp: FINAL FANTASY XIV 1.23b client and network decompilation](https://awesomerea.org/resources/meteor-ffxiv-decomp-case/index.md) · Case study
- [Metroid II: byte-matching Game Boy disassembly](https://awesomerea.org/resources/metroid-ii-disasm/index.md) · Case study
- [Metroid Prime: the PrimeDecomp matching GameCube decompilation](https://awesomerea.org/resources/primedecomp-metroid-prime-decomp-case/index.md) · Case study
- [Metroid: byte-matched NES disassembly](https://awesomerea.org/resources/metroid-nes-disasm/index.md) · Case study
- [mgs_reversing: matching Metal Gear Solid Integral source reconstruction](https://awesomerea.org/resources/mgs-reversing-case/index.md) · Case study
- [mh4u-decomp: matching-decompilation progress for Monster Hunter 4 Ultimate](https://awesomerea.org/resources/mh4u-progress/index.md) · Case study

## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.