# Little Planet: Sonic CD recompiled from a matching disassembly > Disassembles every executable file on the Sonic CD disc from runtime coverage and recursive descent, reassembles them byte-identically, and translates the code statically to C on a from-scratch Mega-CD runtime that replaces the BIOS with a high-level implementation. Recompiled blocks run only where memory still holds the code they came from, and a script compares 96 stage runs frame by frame against the interpreter. The project also patches in widescreen and per-zone saves; results remain project-reported. - Type: Case study - Targets: Game - Category: Independent reconstruction cases - Relationship: Independent reconstruction project - Sources reviewed: 2026-10-18 - Added to the catalog: 2026-10-18 - Original resource: - Primary source: - Catalog page: - Record JSON: - Chinese version: [简体中文](https://awesomerea.org/zh/resources/little-planet-sonic-cd-recomp-case/index.md) ## Requirements & limits - **Prerequisites:** Supply your own Sonic CD disc image (cue/bin, iso, ccd/img/sub, chd, or cue with compressed audio). The Japanese G-6021 release, identified by a data-track SHA-1 in README, is the tested one; other releases boot but are untested. No BIOS dump is needed, and no disc data is included. - **Prerequisites:** Releases target Windows x64 (installer or portable zip), macOS 11+ (not notarized) and Linux x86_64/ARM64 AppImages. Source builds need Python (3.10+ on Windows) and SDL3, with Visual Studio 2022 Build Tools, Xcode command-line tools or gcc/g++. The optional remastered opening also needs a separately built FFmpeg and a fetched video. - **Scope:** README reports that all 112 executable files reassemble byte-identically to the Japanese release, that 622k instructions recompile into 22,897 blocks, and that boot, gameplay, audio and bit-exact save states work. The disassembly is code only; graphics, sound and level data stay on the user’s disc. True16:9 widescreen and saves after every zone patch the game’s own programs, so those options depart from the original game. - **Testing evidence:** README documents tools/decomp.sh for extracting the disc, reassembling asm/ and comparing each file; tests/rc_check.sh compares per-frame RAM and CPU-PC hashes of recompiled and --interp runs across 96 scripted stages. README also reports SingleStepTests results: all 1.6M Z80 cases, and all 1M 68000 cases apart from some undocumented DIVS/ASR and address-error cases. CI tests only a homebrew test disc. - **License:** MIT covers the runtime, tools and installer. third_party/ code, the bundled LGPL 2.1 FFmpeg and LuanUP’s remastered opening, included with permission, keep their own terms, and nothing extracted from a disc is covered. The reviewed LICENSE’s exclusion note names Star Fox 2 rather than Sonic CD. The project is unofficial, unaffiliated with Sega. ## Primary sources 1. 2. 3. 4. 5. ## More in Games - [Lost Odyssey Recomp: statically recompiling an Xbox 360 RPG into native ports](https://awesomerea.org/resources/lost-odyssey-recomp-case/index.md) · Case study - [MarioKart 64: Recompiled — a native port through N64Recomp static recompilation](https://awesomerea.org/resources/mariokart64-recompiled-case/index.md) · Case study - [MediEvil Recomp: a PlayStation static recompilation to C#](https://awesomerea.org/resources/medievil-recomp-case/index.md) · Case study - [Mega Man X Recompiled: a snesrecomp static recompilation](https://awesomerea.org/resources/megaman-x-snes-recomp-case/index.md) · Case study - [Melee Unlocked: a Windows source port and static recompilation of Melee](https://awesomerea.org/resources/melee-unlocked-case/index.md) · Case study - [Pinyon Shift: a ShiftGlue static recompilation of Forza Horizon for PC](https://awesomerea.org/resources/pinyon-shift-forza-horizon-recomp-case/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.