Conker's Bad Fur Day Recompiled

Conker's Bad Fur Day: Recompiled

A native PC port of Conker's Bad Fur Day (N64, US version). It's built by statically recompiling the game with N64Recomp, starting from the Conker decompilation. It runs on N64ModernRuntime and is rendered by RT64.

This repository contains no game data. You need your own legally obtained copy of the US ROM. Everything from the game is extracted from that ROM on your machine during the build.

Download

Ready-to-play Windows, Linux and macOS (Apple Silicon, macOS 15 or later) builds are on the Releases page. Unpack one anywhere, run ConkerRecomp, and pick your US ROM in the launcher the first time. The packages contain no game data: you still need your own ROM. The macOS app isn't signed with an Apple developer ID, so the first time, open it and then choose Open Anyway in System Settings > Privacy & Security. To build it yourself instead, read on.

Features

• Runs natively on Windows (Direct3D 12 or Vulkan), Linux (Vulkan) and macOS

  (Metal), rendered by RT64. Supports higher resolutions, widescreen, anti-aliasing and high frame-rate presentation.

• Game controllers and keyboard, with remappable controls and rumble.
• Full audio: music, sound effects and the voice acting.
• Saving (EEPROM), stored per user.
• A launcher with settings, controls and a mod menu (RecompFrontend, as in

  Zelda 64: Recompiled and Banjo: Recompiled).

• Mod support (.nrm mods: function patches and hooks). Three mods are

  included: Skip Intro, Skip Any Cutscene and Cheats.

• Texture packs (RT64's .rtz), for HD textures and other replacements.

Status

The game is playable, and has been played through to the end. Known issues:

• Widescreen: the pause menu's blurred background is the 4:3 frame scaled up to

  the full width, so its top and bottom are cropped.

• Environment-mapped (reflective) surfaces render without their reflection texture.
• Frame rates above 30: characters snap once when the game changes how many parts

  it draws them with, a few times a minute, and the camera can blend across a cut.

• Only the US ROM is supported (and ROM hacks that only change its assets: see

  ROM hacks).

• Linux: the build and the game have been tested on Ubuntu 24.04 under WSL, with

  software Vulkan (llvmpipe) and sound. It hasn't been played on Linux with a real GPU driver yet, so reports are welcome, especially about performance or audio (under WSL the sound crackles while the software renderer loads the CPU).

• macOS: the build has been tested on an Apple M3 Pro with macOS 27 and Xcode 27,

  and the game starts and runs with Metal. It hasn't been played through on macOS yet, and Intel Macs haven't been tried.

If the game crashes on Windows, a report is written to crash.log next to the executable and shown in a message box. On Linux and macOS, the crash report is printed to the terminal. Please include it when reporting a problem.

What you need to build it

• The US ROM of Conker's Bad Fur Day in big-endian .z64 format, with

  SHA-1 4cbadd3c4e0729dec46af64ad018050eada4f47a. It is never committed: the build extracts what it needs from your copy.

• A folder path without an apostrophe (') to clone into. Some of RT64's build

  steps break on one.

Then follow the guide for your system: Windows, Linux or macOS. Each is one command once the tools are installed. The first full build takes a while, because the recompiled game is a lot of C code.

Building on Windows

Windows 10 or 11 (x64). Everything builds natively; build.cmd does all of it.

1. Install the tools (once)

• Git for Windows.
• Python 3. In the installer, tick *Add

  python.exe to PATH*.

• Visual Studio 2022 or later with the Desktop development with C++

  workload. The free Build Tools for Visual Studio edition is enough.

2. Get the code and build

In a Command Prompt, in the folder you want it in (for example D:\Games), with the path to your ROM:

git clone --recursive https://github.com/sciaschi/CBFD-Recompiled.git
cd CBFD-Recompiled
build.cmd "C:\path\to\your\conker.z64"

The first build takes a while. When it's done, the game is host\build-win\ConkerRecomp.exe (see Playing).

Updating

git pull
build.cmd

The script updates the submodules and their patches, and only rebuilds what changed.

Building on Linux

Tested on Ubuntu 24.04 (x86-64). You need a Vulkan driver: Mesa's, which most distributions install by default, or NVIDIA's.

git clone --recursive https://github.com/sciaschi/CBFD-Recompiled.git
cd CBFD-Recompiled
./build.sh ~/path/to/your/conker.z64

On Ubuntu and Debian, the script lists the packages it's missing and offers to install them. On other distributions, install the equivalents of git python3 cmake ninja-build clang pkg-config libsdl2-dev libdbus-1-dev libfreetype-dev yourself. When it's done, run host/build/ConkerRecomp (see Playing).

To update: git pull, then ./build.sh again.

Building on macOS

macOS on Apple Silicon or Intel. The game renders with Metal. build.sh does all of it, as on Linux.

1. Install the tools (once)

• Xcode, from the App Store. The Command Line Tools alone aren't enough: RT64

  compiles its shaders with Xcode's Metal compiler. Open Xcode once to finish its setup. If xcode-select -p doesn't print a path inside Xcode.app, run sudo xcode-select -s /Applications/Xcode.app.

• Homebrew.
• Optionally, for building mods: brew install llvm (Apple's clang can't compile

  for the N64's MIPS processor).

2. Get the code and build

In Terminal, in the folder you want it in, with the path to your ROM:

git clone --recursive https://github.com/sciaschi/CBFD-Recompiled.git
cd CBFD-Recompiled
./build.sh ~/path/to/your/conker.z64

Put the ROM's path in quotes if it has spaces or an apostrophe, for example ./build.sh "$HOME/Downloads/Conker's Bad Fur Day (USA).z64".

The first build takes a while. If some tools are missing, the script lists the Homebrew packages (cmake ninja pkg-config sdl2 freetype) and offers to install them. It also offers to download Xcode's Metal Toolchain (about 850 MB), which Xcode 26 and later install separately. When it's done, the game is host/build/ConkerRecomp (see Playing).

To turn it into a standalone ConkerRecomp.app that runs without Homebrew (as the release workflow does), run sh host/package_macos.sh after brew install dylibbundler. The app ends up in host/build/.

Updating

git pull
./build.sh

The script updates the submodules and their patches, and only rebuilds what changed.

What the build does

build.sh holds the full sequence, if you'd rather run the steps yourself:

1. Checks your ROM (copied to conker/baserom.us.z64) and applies the patches in

   recomp/ to N64Recomp, N64ModernRuntime and RT64.

2. Builds N64Recomp.
3. Runs recomp/recompile.py, which unpacks the game's code from your ROM and

   recompiles it into RecompiledFuncs/. Which functions there are, and where, comes from recomp/conker.us.syms.toml: names, addresses and sizes, but no code. The code itself only ever comes from your ROM.

4. Builds the game (host/) with CMake.

Working on the decompilation

recomp/conker.us.syms.toml (and mods/syms/) are generated from the decompilation in conker/, which needs its own Linux tools: IDO, which runs through the MIPS binutils, and the Python packages in requirements.txt. On Linux, macOS, or in WSL on Windows, ./build.sh --decomp builds the decompilation too, checks that it rebuilds your ROM's code byte for byte, and regenerates those files from it (recomp/run.sh). The decompilation is a work in progress: about 9% of the code is C so far, and the rest is still the original assembly.

On macOS, --decomp also needs coreutils and mips-linux-gnu-binutils from Homebrew (the script offers to install them). The decompilation comes with two Linux programs, the IDO compiler and a patched gzip that compresses exactly as the original game's did, so the script puts macOS replacements in tools/macos/: IDO's macOS build from ido-static-recomp, and GNU gzip 1.10 built with the same one-line change.

Playing

Run host/build/ConkerRecomp (Linux and macOS) or host\build-win\ConkerRecomp.exe (Windows). The first time, pick Load ROM in the launcher and select your ROM (the same baserom.us.z64 works). After that it's remembered, so just choose Start Game.

• Settings (in the launcher, or Esc / the controller's menu button in game)

  has graphics (resolution, aspect ratio, anti-aliasing, frame rate), controls, sound and mod options.

• Saves, settings and the stored ROM live in ~/.config/ConkerRecompiled on

  Linux, ~/Library/Application Support/ConkerRecompiled on macOS and %LOCALAPPDATA%\ConkerRecompiled on Windows. Put an empty portable.txt next to the executable to keep them there instead.

• Default keyboard controls: move with WASD, A = Space, B = Left Shift,

  Z = Q, L = E, R = R, Start = Enter, C buttons = arrow keys, D-pad = IJKL. Everything can be remapped in Controls.

• N64 pads and adapters for real N64 controllers (raphnet-tech's, Mayflash,

  Hyperkin, the NSO and 8BitDo 64 controllers) are mapped from assets/controllerdb.txt, with the C buttons as the right stick. A controller SDL doesn't know can be given a mapping in the SDL_GAMECONTROLLERCONFIG environment variable, which takes precedence.

ROM hacks

A ROM hack that only changes the game's assets (its audio, textures, models or text), such as an uncensored patch that restores the bleeped words, plays like the US ROM. The recompiled code only comes from the ROM's code, which has to be the US ROM's, so hacks that change the game's code are refused.

The launcher's Version option says which ROM is in play, with its region (for example Version: US Original or Version: US Uncensored), and so does the window's title. Add ROM loads another: pick the hack's .z64, and it's put in play. After that, selecting Version switches between the ROMs you've loaded. Other regions' ROMs (such as the European one) are refused, with a message naming the region. Each is kept in rom_versions/ in the data folder (64 MB apiece). Saves are shared between them.

Mods

Mods are .nrm files. Install one by copying it into the mods folder of the data folder above (or dropping it onto the Mods menu), then enable it in the Mods menu. Some mods have options there too.

Each release has the included mods built, in its Mods zip (the same .nrm files work on every system). Their source is in mods/. Build one on Linux, macOS (which also needs brew install llvm lld, as Apple's clang can't compile for MIPS) or in WSL, from the repository root, after recomp/run.sh. It links with ld.lld (sudo apt install lld), or GNU ld (mips-linux-gnu-ld) where there's none, but GNU ld can't link a mod that calls the game's functions, such as Skip Intro:

sh mods/build_mod.sh mods/skip_cutscenes

The .nrm ends up in the mod's build/ folder.

• Skip Intro (mods/skip_intro): boots straight to the main menu, skipping

  the notices, logos and the chainsaw opening.

• Skip Any Cutscene (mods/skip_cutscenes): L skips a cutscene even the

  first time you see it. An option also allows skipping the ones the game never lets you skip.

• Cheats (mods/cheats): infinite health, infinite lives and a full wallet,

  each toggled in the mod's options.

Writing your own is covered in recomp/README.md.

Texture packs

Texture packs replace the game's textures with new ones, such as HD textures. They're RT64 texture packs, the same format as Zelda 64: Recompiled's and Banjo: Recompiled's: an rt64.json listing each texture's hash and its replacement image. Install a .rtz pack like a mod (the mods folder, or dropped onto the Mods menu), then pick it in Settings > Texture Packs, which turns it on and the other packs off. Packs installed while the game runs are listed there from the next start. Its default, Set in the Mods Menu, leaves them to the Mods menu instead, where several can be on at once (later ones in the list take precedence).

GLideN64 texture packs (for Project64 and RetroArch) work too. Install the pack's .htc file the same way (Install Mods or dropped onto the Mods menu), or put it in the mods folder and start the game or press the Mods menu's refresh button: it's unpacked, once, into a pack folder beside it, with its progress shown (a large pack takes a minute or so), and turned on. It's then in the Mods menu, and listed in Settings > Texture Packs. GLideN64 names each texture by a different hash than RT64 (Rice's), which the game's RT64 works out as each texture is loaded. Only packs stored as RGBA8 are unpacked (not those built with texture compression).

tools/texture_packs/gliden64_to_rt64.py makes a .rtz from a GLideN64 pack (a .htc, or a folder of ...#crc#format#size_all.png files) to share:

python tools/texture_packs/gliden64_to_rt64.py pack.htc --out my_pack --name "My Pack" --author Me --rtz my_pack.rtz

Given folders of textures dumped while playing (RT64's developer mode, below: F1, Start dumping textures), it instead lists the dumped textures with RT64's hashes, as RT64 without live matching needs (see the tool).

To make a pack from scratch, put a folder in mods with a mod.json ("game_id": "conker", plus an id, version, display_name, authors and minimum_recomp_version) and an rt64.json:

{ "configuration": { "configurationVersion": 3, "hashVersion": 5 }, "textures": [] }

With it enabled, and RT64's developer mode on ("developer_mode": true in graphics.json in the data folder), RT64's inspector (F1) shows each draw's texture hash and has a Replace button that picks an image and adds it to the folder's rt64.json. Zip the folder's contents (without mod.json) and rename it to .rtz to share it.

How it works

recomp/README.md documents the whole pipeline:

• how the decomp's ELF is prepared for N64Recomp (recomp/prepare_elf.py);
• the recompiler configuration and hooks (conker.toml);
• the audio microcode;
• the changes to N64Recomp, N64ModernRuntime and RT64 (Conker's graphics

  microcode, widescreen);

• the host application in host/;
• debugging tools.

AI assistance

This project was made with heavy use of an AI coding assistant (Claude, through Claude Code). That covers the recompilation setup, the patches to the tools, the host application, the mods, and the functions decompiled to C in this repository.

What's checked, and how:

• Decompiled C is only kept when it compiles to exactly the original

  instructions. The build fails unless the rebuilt code is byte-for-byte identical to the ROM's.

• The port is checked by playing it, and by comparing its behaviour with

  the original running in an emulator.

What isn't checked: names, types and comments don't change the compiled bytes, so a byte-for-byte match says nothing about whether they're right. Names that end in an address (for example resetSlotState_150104F0) are best guesses based on what the code appears to do. Treat them as hints, not established facts.

This is an independent project. The AI-assisted work here isn't part of the upstream decompilation, and the people behind that project and other N64 decompilation communities aren't responsible for it. Please report problems here, not to them.

Contributing

Bug reports, fixes and patches are welcome: see CONTRIBUTING.md.

Credits

• The Conker's Bad Fur Day decompilation project,

  whose work this is built on.

• The macOS port, and support for ROM hacks, by

  nitrostemp.

• N64Recomp,

  N64ModernRuntime and RecompFrontend by Wiseguy and contributors.

• RT64 by Darío and contributors.
• The mod headers follow the

  Banjo: Recompiled mod template.

• Fonts: Inter, Noto Emoji

  and promptfont.

License

This project's own code is under the MIT License. The submodules keep their own licenses, and a build combines them:

• N64ModernRuntime (librecomp and ultramodern) is under the

  GPL, version 3. As the program includes it, the program as a whole is distributed under the GPL version 3, which gives everyone who gets it the right to its source: this repository, at the release's tag. The release packages include the GPL's text (LICENSE-GPL-3.0.txt) and LICENSES.txt, which lists them.

• RT64 is under the MIT License, but the live texture pack matching that

  recomp/rt64.patch adds (src/hle/rt64_rice_hash.cpp) is under the GPL, version 2 or later: it imitates the Rice texture hashing of GlideHQ (Hiroshi Morii, as in GLideN64) and Rice Video, both under the GPL version 2 or later (recomp/README.md). That's compatible with the GPL version 3.

The game itself is not included and not covered by them.

Conker's Bad Fur Day is © Rare Ltd. This project is not affiliated with or endorsed by Rare, Microsoft or Nintendo.