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Kotlin Multiplatform + Compose Multiplatform CLAUDE.md

CLAUDE.md for Kotlin Multiplatform apps sharing UI with Compose Multiplatform across Android, iOS, desktop, and web.

Claude Code (CLAUDE.md)Kotlin Multiplatform

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Save this as CLAUDE.md in your repository root, commit it, and your agent will pick it up automatically. Edit the commands to match your project.

# CLAUDE.md: KMP + Compose Multiplatform

## Commands
- `./gradlew :composeApp:assembleDebug` (Android) · `./gradlew :composeApp:run` (desktop) · `./gradlew allTests` · `./gradlew detekt` or `ktlintCheck`
- iOS: open `iosApp/iosApp.xcodeproj` or `./gradlew :composeApp:iosSimulatorArm64Test`

## Structure
- `composeApp/src/commonMain`: shared UI (Compose), ViewModels, navigation, resources.
- `shared/` or `core/*` modules: domain, data (Ktor, SQLDelight/Room KMP, DataStore), DI (Koin).
- Platform folders (`androidMain`, `iosMain`, `desktopMain`, `wasmJsMain`) only for platform glue.

## Rules
- Default to `commonMain`. Before writing `expect`/`actual`, check for a multiplatform library.
- Resources via Compose Multiplatform resources (`Res.string.title`, `Res.drawable.logo`) in `composeResources/`, not Android `R`.
- ViewModels from `androidx.lifecycle` (multiplatform) exposing `StateFlow` UI state; collect with `collectAsStateWithLifecycle()`.
- Navigation with the multiplatform Navigation Compose library and `@Serializable` routes.
- No `java.*`/`android.*` imports in common code; use kotlinx-datetime, kotlinx-io, Okio.
- Keep the iOS entry (`MainViewController`) thin; Swift code only for things Compose can't do.
- Dependencies in `gradle/libs.versions.toml`; keep Kotlin, Compose plugin and AGP versions compatible (check the compatibility table before bumping).

## Tests
`commonTest` with `kotlin.test`, `runTest`, and Turbine for flows; UI tests with the Compose multiplatform test APIs.