By the end of this page your project will run on the Crimson modular base classes - ready for Game Features, plugins, and the rest of the suite to extend your actors. That's the one broadly-useful adoption step CrimsonCommon needs; everything else it provides is opt-in.
CrimsonCommon is a toolbox, not a pipeline
It is a foundation of independent contracts and utilities - tag stacks, the message bus, the ability-set bridge, UI layers, and more. None of them are required. Adopt the base classes below to anchor your project, then pull in only the pieces you need from the How-To pages.
Prerequisites
A UE 5.8 project (Blueprint or C++). Nothing else - CrimsonCommon has no sibling Crimson dependency to enable alongside it.
1. Enable the plugin
Open Edit -> Plugins, type Crimson in the search box, tick CrimsonCommon's checkbox, and restart the editor when prompted. For a Blueprint project that's the entire install - you never hand-edit the .uproject or any .Build.cs.
C++ projects: after enabling the plugin, add its module to your build file so your game code can use its types. Any plugin that uses the CRIMSON_LOG_* macros must also list it here.
csharp
// YourGame.Build.cs
PublicDependencyModuleNames.Add("CrimsonCommon");
Verify
CrimsonCommon shows as enabled in the Plugins window and the editor restarts without errors.
2. Swap to the modular base classes
Replace Unreal's default framework classes with the Crimson modular equivalents. These add Game Feature extension hooks (so plugins and Game Features can attach components/abilities) and otherwise behave exactly like their Epic bases.
Reparent your framework Blueprints to the ACrimsonModular* classes, or set them in Project Settings -> Maps & Modes / your Game Mode.
Adopt incrementally
You don't have to swap everything at once. The base classes are independent - reparent the Character today and the Player State later. Use only the ones you need.
Verify
Play in editor. Your pawn/controller behave as before, and Game Feature actions targeting these classes can now attach to them.
What's next - pick the capabilities you need
Each of these is independent; use any, all, or none. Track networked counts with How-To: Track Counts with Tag Stacks, grant abilities across plugins with How-To: Grant an Ability Set, make actors interactable with How-To: Make an Actor Interactable, send cross-plugin events with How-To: Broadcast & Listen for Messages, drive UI layers with How-To: Show a Widget on a UI Layer, or learn the model behind it all in Concept: Decoupling Patterns.