While the game natively supports mods, this would have had us limited to replacing already existing items, but we wanted flying cars. So a bunch of brilliant people drilled deep into the code of Cyberpunk 2077 and created a bunch of tools that let us do more.
The most prominent example of a core mod is the Skyrim Script Extender — fortunately, Cyberpunk 2077 is rather more stable.
Since this kind of mod interacts with the game on such a fundamental level, they are prone to breaking whenever CDPR changes their API. This is the reason why game updates break mods — we recommend to turn off auto-update and manually upgrading once the core mods you need have been brought up-to-date.
Redscript (Nexus | GitHub) is an open-source programming language and toolkit (currently includes a compiler, a decompiler and a disassembler), natively working with Cyberpunk 2077's scripting runtime.
The scripts are compiled into a binary format recognizable by the game engine. The final blob includes original game scripts with all changes from the mods, and replaces original r6/cache/final.redscripts or r6/cache/modded/final.redscripts.
Redscript supports importing native types and functions registered by mods based on RED4ext.SDK, allowing modders to extend scripting runtime functionality.
Some examples for existing mod include, but are not limited to
Cyber Engine Tweaks (Nexus | GitHub) is a framework with a LUA wrapper, which will let you access anything exposed via RTTI, i.e. all scripted and native types and functions, including those added using redscript and RED4ext. On top of that, it lets you bind hotkeys for custom functions and interact with the game's TweakDB database at runtime.
Changes made via CET's Tweak Browser are not persistent, because the TweakDB gets changed at run-time. You can use TweakXL or create a CET mod to apply your changes each time the TweakDB is initialized.
Lots of mods and scripts run on top of CET, tweaking the game in various ways from changing the weather to adding a wardrobe system before CDPR added one.
The perhaps most prominent example is Appearance Menu Mod (wiki | Nexus), which turns Cyberpunk 2077 into The Sims: Capitalist Dystopia.
RED4ext
RED4ext (Nexus | GitHub) is Cyberpunk 2077's equivalent to Skyrim Script Extender. It consists of two parts:
RED4ext Loader – Loads and manages .dll plugins from red4ext/plugins. Provides essential functions such as game version checking, logging, hooking, and some REDengine 4 specific helpers for plugins.
RED4ext.SDK – Contains the reversed engineered types and helpers to extend the engine. It can also be used independently of RED4ext loader. Originally written in C++, but there's also a Rust binding.
With RED4ext >= 1.13, you no longer need cybercmd. Make sure to uninstall it!
ArchiveXL (Nexus | GitHub) allows modders to load custom resources into Cyberpunk 2077. Working under the hood, it is the essential tool to add and extend rather than replace. It also includes script extensions to, for example, load UI widgets from any resources than only those available to the current context.
TweakXL (Nexus | GitHub) allows modders to modify TweakDB in the form of .yaml or .tweak files. It also adds a scripting API allowing redscript mods to apply changes during TweakDB initialization or dynamically.
Codeware
Requires RED4ext.
Codeware (Nexus | GitHub) is a library and framework for redscript and Cyber Engine Tweaks mods. It exposes many engine types and functions that are not available by default and adds new functionalities regarding many aspects of the game, such as:
game events and life cycle
spawning game objects
manipulating world states
building UI widgets
accessing type information
... and much more.
Equipment-EX
Equipment-EX (Nexus | GitHub) makes use of every single one of the frameworks mentioned above to overhaul CDPR's wardrobe system. Extending it from 6 slots to more than 30, it lets you save an unlimited number of outfits and supports modded items.
RedFileSystem
Requires RED4ext.
RedFileSystem (Nexus | GitHub) is a library for redscript and Cyber Engine Tweaks mods. It exposes functions to read / write with the file system. It supports UTF8 text and Json formats. Modders can create, read and write files within game's directory. It can be useful to store custom data, for example in a mod's directory.
It will tell you which .reds files it has been loading, and if any of them failed.
Please note the warning in the log:
If the mod is working, ignore it
If the mod isn't working, this tells you what to check. You can't have mods installed twice!
If all goes well, it will look like this:
[INFO - Sat, 22 Apr 2023 10:08:08 +0100] Using defaults for the script manifest (manifest not present)
[INFO - Sat, 22 Apr 2023 10:08:08 +0100] Compiling files: C:\Games\Cyberpunk 2077\r6\scripts\a-bunch-of-stores-atelier-store.reds, C:\Games\Cyberpunk 2077\r6\scripts\virtual-atelier\vendor-preview\GarmentItemPreview.reds
[WARN - Sat, 22 Apr 2023 10:08:08 +0100] At C:\Games\Cyberpunk 2077\r6\scripts\appearanceChangeUnlocker\mirrorUnlocker.reds:38:1:
@addField(inkScrollArea)
^^^
field with this name is already defined in the class, this will have no effect
(a bunch of these warnings)
[INFO - Sat, 22 Apr 2023 10:08:08 +0100] Compilation complete
[INFO - Sat, 22 Apr 2023 10:08:08 +0100] Output successfully saved in C:\Games\Cyberpunk 2077\r6\cache
Logs: RED4ext
Cyberpunk 2077\red4ext\logs\red4ext.log
It will tell you which of the plugin DLLs it has been loading.
If all goes well, it will look like this (version numbers are fake):
[2023-04-22 10:08:05.698] [RED4ext] [info] RED4ext (v4.7.11) is initializing...
[2023-04-22 10:08:05.698] [RED4ext] [info] Game patch: 4.511 Hotfix 999
[2023-04-22 10:08:05.698] [RED4ext] [info] Product version: 4.511
[2023-04-22 10:08:05.698] [RED4ext] [info] File version: 4.7.11.13361
[2023-04-22 10:08:05.717] [RED4ext] [info] RED4ext has been successfully initialized
[2023-04-22 10:08:05.816] [RED4ext] [info] RED4ext is starting up...
[2023-04-22 10:08:05.816] [RED4ext] [info] Loading plugins...
[2023-04-22 10:08:05.816] [RED4ext] [info] Loading plugin from 'C:\Games\Cyberpunk 2077\red4ext\plugins\ArchiveXL\ArchiveXL.dll'...
[2023-04-22 10:08:05.874] [RED4ext] [info] ArchiveXL (version: 4.7.11, author(s): psiberx) has been loaded
[2023-04-22 10:08:05.874] [RED4ext] [info] Loading plugin from 'C:\Games\Cyberpunk 2077\red4ext\plugins\Codeware\Codeware.dll'...
[2023-04-22 10:08:06.180] [RED4ext] [info] Codeware (version: 5.7.11, author(s): psiberx) has been loaded
[2023-04-22 10:08:06.180] [RED4ext] [info] Loading plugin from 'C:\Games\Cyberpunk 2077\red4ext\plugins\RedHotTools\RedHotTools.dll'...
[2023-04-22 10:08:06.262] [RED4ext] [info] RedHotTools (version: 1.6.11, author(s): psiberx) has been loaded
[2023-04-22 10:08:06.263] [RED4ext] [info] Loading plugin from 'C:\Games\Cyberpunk 2077\red4ext\plugins\TweakXL\TweakXL.dll'...
[2023-04-22 10:08:06.291] [RED4ext] [info] TweakXL (version: 4.8.12, author(s): psiberx) has been loaded
[2023-04-22 10:08:06.291] [RED4ext] [info] 4 plugin(s) loaded
[2023-04-22 10:08:06.291] [RED4ext] [info] RED4ext has been started
[2023-04-22 10:09:13.572] [RED4ext] [info] RED4ext is shutting down...
[2023-04-22 10:09:14.297] [RED4ext] [info] ArchiveXL has been unloaded
[2023-04-22 10:09:14.322] [RED4ext] [info] TweakXL has been unloaded
[2023-04-22 10:09:14.353] [RED4ext] [info] RedHotTools has been unloaded
[2023-04-22 10:09:14.468] [RED4ext] [info] Codeware has been unloaded
[2023-04-22 10:09:14.469] [RED4ext] [info] 4 plugin(s) unloaded
[2023-04-22 10:09:14.488] [RED4ext] [info] RED4ext has been shut down
Tells you which tweaks have been read and processed, pointing out errors and warnings in the process. If your custom item additions don't work, you might find a hint here.
If it loads correctly, you will see something like this:
