Compose Expert

This handles the visual layer of Compose Multiplatform projects, covering shared UI components, state management patterns like remember and derivedStateOf, and Material3 theming. The core philosophy is simple: default to sharing in commonMain unless you need platform-specific system APIs. It draws clean boundaries with other skills, delegating navigation structure to platform experts and Kotlin language details to kotlin-expert while focusing on the composable layer itself. The state hoisting patterns and recomposition optimization guidance are solid, especially the derivedStateOf examples for scroll performance. Useful when you're deciding what belongs in shared UI versus platform-specific code, or when you need reference patterns for stateless composables that work across Android and Desktop.