kotlin-coroutines

Use Dispatchers.Main for UI updates, Dispatchers.IO for blocking I/O like network and database calls, and Dispatchers.Default for CPU-intensive work. Inject dispatchers via a DispatcherProvider interface instead of hardcoding them so tests can substitute test dispatchers.

Replace GlobalScope with a lifecycle-bound scope such as viewModelScope in ViewModels or lifecycleScope in UI components. For work that must outlive the screen, use WorkManager or an explicit Application-scoped class with named start and stop methods.

Catching generic Exception or Throwable also catches CancellationException, which silently breaks structured cancellation so parent scopes cannot stop the coroutine. Catch only specific types like IOException, and always rethrow CancellationException.

StandardTestDispatcher queues coroutines until you call advanceUntilIdle, giving precise control over execution order and delays. UnconfinedTestDispatcher runs coroutines eagerly, which is simpler for basic state tests but can hide ordering bugs.

No, runCatching catches all Throwable including CancellationException, breaking structured concurrency. Use a suspendRunCatching utility that rethrows CancellationException, or use try/catch with specific exception types instead.

Repositories should expose suspend functions and let the caller own the scope, because a stored CoroutineScope hides cancellation, error reporting, and lifecycle ownership. Only UI state holders using lifecycle-bound scopes for UI events should launch from non-suspending methods.