Decompiling the Darktide Source Code

Thanks to smart people, we have the tools to decompile the source code for Warhammer 40,000: Darktide into readable Lua code.

These tools come with instructions, but lazy people (people) get annoyed at having to read two documents (oh the horror), so I just collated them into this page for convenience. Consequently, I don't cover every single option because that's more reading.

Because of my current setup, these instructions will be written from a Windows perspective. I'm assuming you are familiar with moving folders and files around, but I'll treat you like an idiot because that's how I like to be treated (wait what who said that).

Requirements

• Darktide installed on your computer
• limn bundle extractor
• luajit decompiler, though I recommend downloading the precompiled older version if you just want it for yourself

Instructions

1. Extract limn and the decompiler to a folder, which I'll call "Decompiling Folder" from now on
   • You can move them so the .exe files are in the same folder, like

   Decompiling Folder
    |
    |---> limn.exe
    |---> README.md
    |---> luajit-decompiler-v2.exe
    |---> luajit-decompiler-v2.pdb
   

   • I had limn in its own folder because I'm lazy
2. Open the command prompt (cmd.exe) or PowerShell
3. (Optional) In the command prompt, move to the Decompiling Folder
   • Otherwise, you'll have to include the full path before running each exe
   • ex: cd "C:\Users\HadronGooner\Documents\Decompiling Folder"
   • Replace the path with wherever you put extracted it
4. Run limn on your Darktide game folder, through the command prompt
   • From the game bundles, extract the bytecode
   • This will dump the bytecode into the out folder
   • ex: limn -i "C:\Program Files (x86)\Steam\steamapps\common\Warhammer 40,000 Darktide\bundle" lua
     • lua means extract only lua files (the code); to include textures and the rest, use * instead
     • That's the default path for Steam; your file path may differ
     • If you own Darktide on Steam, you can just run limn lua and let it automatically find your game for you
5. Run luajit-decompiler on the out folder
   • This dumps the lua code into the output folder
   • ex: luajit-decompiler-v2.exe out -m
     • This is assuming you put the .exe files in the same folder, as written in step 1
     • -m means minimize changes, so it adds trailing commas and stuff (this doesn't really matter for us but it's how it's done in Aussiemoon's repository to share with us)
6. You're done! Read the output with your method of choice

Uploading These Files

The Darktide community hosts a copy of these in a GitHub repository, maintained by Aussiemoon. If you decompiled the code before Aussiemoon caught up to the latest patch, you can make a pull request (PR), if you have a GitHub account.

1. Fork the repository
2. Clone your fork locally
   • GitHub doesn't let you upload more than 100 files at once, so uploading it through local git tools is much easier
   • Where you download it to doesn't really matter
3. Replace the contents of your fork (besides the README) with the contents of the output folder
   • Make sure you used the -m flag when you ran the decompiler!
   • Make sure you're using the latest decompiler version!
   • Otherwise there will be unecessary differences and you'll have to redo the PR
   • Delete all, then add all
   • This way you catch if something was deleted
4. Upload it with git
   • I used the VS Code Extension
   • Whatever it is, you'll be able to upload them all at once
5. Make a PR
   1. Compare across forks
   2. Select the main branch of your fork
   3. Fill out and submit the PR