UE Module & Build System

Target engine: UE 5.8. APIs below are verified against the 5.8 headers and UnrealBuildTool sources; older forms are listed under "Deprecated — do not use".

This skill covers UnrealBuildTool (UBT) ModuleRules (*.Build.cs) and TargetRules (*.Target.cs), the .uproject and .uplugin descriptors, module registration (IModuleInterface and IMPLEMENT_MODULE in Modules/ModuleManager.h, module Core), plugin discovery (IPluginManager in Interfaces/IPluginManager.h, module Projects), and the compiler, linker, UHT and UBT errors those files cause.

Context

Read .agents/ue-project-context.md if it exists (module names, conventions, enabled plugins, GAS/networking setup). Do not stop if it is missing.

Identify the area from the request and the codebase. Ask only when two plausible readings would produce different code.