android-data-layer

Create a repository that exposes a Flow from the Room DAO as the single source of truth and a suspend refresh function that fetches from the network and writes to the database. Bind the implementation to its interface with a Hilt @Binds module.

Return Flow for queries the UI observes, since Room re-emits automatically when the table changes. Use suspend functions for one-shot reads and all mutations like inserts, updates, and deletes.

Yes, Room has been KMP-stable since version 2.7.0. You need @ConstructedBy on the database, the BundledSQLiteDriver for consistent SQLite versions, setQueryCoroutineContext(Dispatchers.IO), and KSP wired per target platform.

Use stale-while-revalidate for reads by observing the local database while triggering a background network refresh. For writes, apply the outbox pattern by saving changes locally and syncing them with a WorkManager job that survives process death.

Letting IOException or HttpException escape forces the ViewModel to import Retrofit and OkHttp types, coupling it to the network implementation. The repository should catch these and map them to sealed domain error types like DataError.

Both conventions are valid. The Entity suffix follows Room convention and ties the name to persistence, while a Cached prefix abstracts the storage mechanism. Match the existing project convention, or default to the Entity suffix.