Windows
29 projects: 6 decompilations, 0 static recompilations, and the rest ports, rewrites and clean-room builds.
Apache POI
Microsoft Office file formats
Java library that reads and writes Word, Excel, PowerPoint, Visio and Outlook files, including the legacy binary formats it originally reverse engineered.
Butterchurn
MilkDrop (Winamp visualiser)
WebGL implementation of the MilkDrop music visualiser that runs existing presets in the browser.
Darkflame Universe
LEGO Universe servers
Server emulator that brings back LEGO Universe, the MMO shut down in 2012, for players with the original client.
Devilution
Diablo
Reconstructed source for Diablo, guided by symbol data left on the Japanese PlayStation port and a debug build hidden in the PC release. DevilutionX grew from it.
DevilutionX
Diablo and Hellfire
Modern, cross-platform Diablo built on the Devilution reconstruction; it needs DIABDAT.MPQ from your copy, or plays the shareware data.
DirtSand
Myst Online: Uru Live servers
Open-source server for Myst Online: Uru Live and the Plasma engine, used by community shards.
EasyRPG Player
RPG Maker 2000/2003 runtime
Free interpreter that runs RPG Maker 2000/2003 games on many platforms without the original runtime.
Graveshift (clean room)
Wave-based zombie survival shooters (original game in that style)
Round-based zombie survival in an original cinema map, plus bot deathmatch, on a Three.js engine derived from the MIT-licensed kino-der-toten project, using only CC0 or generated art and sound.
GTA2 RE
Grand Theft Auto 2
Reimplements the PC GTA2 10.5 executable function by function, compiled with Visual C++ 6 to match the original code, and can run either standalone or patched into the retail exe.
JS Paint
Microsoft Paint
Web remake of classic MS Paint that copies its tools and look, adding extras such as unlimited undo and multi-user editing.
LEGO Island decompilation (isle)
LEGO Island
A complete decompilation of LEGO Island 1.1 that aims for instruction-level accuracy with the original Visual C++ 4.2 build; a portable fork grew from it.
LibreDWG
AutoCAD DWG format
GNU library and command-line tools to read and write AutoCAD DWG drawings, built from format documentation and reverse engineering.
Mono
Microsoft .NET Framework
Open-source implementation of the .NET runtime and class libraries, built from the ECMA standards; development has since moved on.
NTFS-3G
Microsoft NTFS file system
Read/write NTFS driver built from reverse engineering of the on-disk format, running in user space via FUSE.
Open Road (clean room)
Late-1990s Need for Speed games (via the OpenNFS engine)
A late-90s arcade racer on OpenNFS compiled to WebAssembly: nine classic circuits keep their geometry with regenerated textures, joined by three original tracks and generic cars.
Open Test Drive Unlimited (OpenTDU)
Test Drive Unlimited
A new Vulkan-based client for the PC version of Test Drive Unlimited, rebuilt game mode by game mode from the original; it runs on top of an owned install's data and aims at modern-system fixes and cross-platform support.
OpenBarnyard
Barnyard (and the TOSHI 2.0 engine)
Decompiles the PC Barnyard game together with Blue Tongue's in-house TOSHI 2.0 engine into buildable C++, with public API docs and a progress tracker.
OpenGMK
GameMaker 8 (Classic) runner
Rust rewrite of the GameMaker Classic runner that plays existing GameMaker 8 executables, with a decompiler and a TAS framework.
OpenNFS
Need for Speed (1990s series)
Scratch-built engine that loads tracks, cars and other assets from the original files of Need for Speed 1-5 and aims to replicate the look and handling of each game.
OpenRCT2
RollerCoaster Tycoon 2
An open-source reimplementation of RollerCoaster Tycoon 2 that began by reverse engineering the original executable function by function, now fully native with multiplayer and new features.
projectM
MilkDrop (Winamp visualiser)
Cross-platform library that reimplements MilkDrop so its presets can drive visualisations in many media players.
Quake III Arena source release
Quake III Arena
id Software's GPL release of the id Tech 3 engine and game code in 2005, which ioquake3 and many later games are built on.
re-plants-vs-zombies
Plants vs. Zombies (GOTY)
Reverse-engineered rebuild of the GOTY Plants vs. Zombies that modernises the old engine and swaps legacy DirectX for a GLFW backend.
Samba
Microsoft SMB/CIFS and Active Directory protocols
Reverse-engineered implementation of Windows file and print sharing and Active Directory domain services.
SpaceCadetPinball
3D Pinball for Windows – Space Cadet
Decompilation of the Windows Space Cadet pinball table that runs natively with SDL2. Normally it needs the original data files.
SWGEmu
Star Wars Galaxies servers
Server emulator recreating Star Wars Galaxies as it played before the 2005 combat overhaul.
Webamp
Winamp 2
Winamp 2 rebuilt in JavaScript for the browser, with classic skin support, playlist and equaliser; embeddable as an npm package.
Wine
Microsoft Windows API
Compatibility layer that reimplements the Windows API so Windows programs run on POSIX systems without a Windows licence.
x64dbg
Windows x86 and x64 user-mode programs
Open-source user-mode debugger for Windows aimed at reverse engineering and malware analysis.