Onboard a future AI session to a specific slice of an existing codebase before a migration, refactor, or extension. Produces onboarding docs under ./onboarding/ — a repo-global glossary that is amended across slices, plus per-slice decision records and (when existing code is affected) a navigation map. Use this skill whenever the user is about to change part of an unfamiliar or inherited codebase and says things like "onboard an agent to this slice", "prepare context before I refactor X", "scope this change", "I'm about to extend/migrate Y", "where do I start in this repo", or "onboard me to this codebase". Reach for it even when the user doesn't say "onboarding" but is clearly trying to build durable context for an upcoming change rather than make the change itself.
Background work patterns for Android/KMP - WorkManager (one-time, periodic, expedited, foreground promotion), foreground services, work observation, Koin WorkerFactory, and the SyncScheduler abstraction. Use this skill whenever implementing background sync, scheduling periodic work, creating a foreground service, observing work progress, setting up WorkManager with Koin, or deciding between WorkManager and foreground services. Trigger on phrases like "WorkManager", "background work", "sync worker", "periodic sync", "foreground service", "schedule sync", "SyncScheduler", "CoroutineWorker", "work observation", "expedited work", or "background sync".
Orchestrates Android development tasks including project creation, deployment, SDK management, and environment diagnostics using the `android` command-line tool.
Compose screen-level architecture for Android/KMP - stability, recomposition strategy, state ownership, side effects, lazy layouts, deferred state reads, and TextField state dispatching. Use this skill whenever architecting a Compose screen's structure, optimizing recomposition at the screen level, deciding state ownership between ViewModel and composables, adding side effects, structuring lazy layouts, or making screen-level performance decisions. This skill is about HOW screens are structured, not how individual components are built — for component construction, see android-compose-components. Trigger on phrases like "recomposition", "stability", "@Stable", "LaunchedEffect", "DisposableEffect", "LazyColumn performance", "collectAsStateWithLifecycle", "derivedStateOf", "screen layout", "Compose performance", "deferred state read", or "state ownership".
Building individual Compose UI components for Android/KMP — IconButton wrapping, project icon objects, previews per state, parameter design, sizing with relative modifiers, theme colors, design system reuse, Material 3 as the base for design-system components, component decomposition, string resources, animations in graphicsLayer, slot composables, and modifier extensions. Use this skill whenever writing or modifying a composable function that is NOT a Root/Screen-level composable: buttons, cards, list items, toolbars, input fields, bottom sheets, dialogs, or any extracted sub-composable. This skill applies every time you write raw Compose UI code for a component — even small ones. For Root/Screen composables, use android-presentation-mvi instead. Trigger on phrases like "create a component", "composable function", "IconButton", "Icon composable", "preview", "modifier extension", "slot API", "design system component", "shared button", "custom icon button", "design-system icon button", "wrap Material 3", "Fill
Koin dependency injection setup for Android/KMP - module definitions per layer, ViewModel injection, assembling modules in :app, and koinViewModel() in composables. Use this skill whenever setting up Koin, defining a DI module, providing a repository or ViewModel, injecting a dependency, or wiring modules in the Application class. Trigger on phrases like "set up Koin", "add a Koin module", "inject a dependency", "DI module", "koinViewModel", "provide a ViewModel", "startKoin", or "single/viewModel/factory".
Integration testing for Android - wire real production classes together (real repositories, real DAOs, real data sources) and only swap test doubles at the boundaries that leave the device: Ktor MockEngine for HTTP, in-memory Room for storage, fake Clock, WorkManagerTestInitHelper for background work. Instrumented tests preferred (no Robolectric). An integration test crosses at least one I/O / process / external-state boundary. Use this skill whenever writing or reviewing tests that touch a database, network, file system, system clock, or background work scheduler. Trigger on phrases like "integration test", "test the repository with Room", "in-memory Room", "Room.inMemoryDatabaseBuilder", "MockEngine", "MockWebServer", "test sync", "test offline-first", "test the data layer", "test the DAO", or "test with a real database".
Set up JaCoCo code-coverage on a Gradle-based Android project — apply the jacoco plugin, pin its tool version (fetched fresh from Maven Central) in the version catalog, and enable unit-test + instrumentation-test coverage on the debug build type so AGP generates the coverage report tasks. It adapts to the project layout: if the project uses convention plugins in `build-logic`/`buildSrc`, it adds a dedicated JaCoCo convention plugin there; for a single-module project without convention plugins it edits the module's `build.gradle(.kts)` directly. Use this skill whenever the user wants to "set up JaCoCo", "configure code coverage", "add coverage to Gradle", "enable test coverage reports", or enable `enableAndroidTestCoverage` / `enableUnitTestCoverage`. The android-instrumentation-coverage skill cross-references this skill to set up coverage on demand. This skill MODIFIES build files (it commits a real setup); for non-invasive, on-the-fly JVM coverage use android-jvm-test-coverage instead.