coroutines-flow

Cold asynchronous streams in Kotlin are modeled using Flow, allowing you to build composable, cancellation-friendly pipelines. You construct streams with flow { }, callbackFlow, or channelFlow to handle producers and emit values sequentially to consumers.

Backpressure and cancellation in Kotlin Flow pipelines are handled using backpressure-aware operators and lifecycle hooks. You apply operators like flowOn, debounce, and onCompletion to manage downstream consumption rates and ensure coroutine cancellation propagates correctly.

Operators like flatMapMerge and transform apply to Kotlin streams by composing sequential processing logic. You chain these operators on a Flow instance to map, filter, debounce, or merge concurrent streams while maintaining asynchronous execution.

Errors and retry logic in asynchronous Kotlin pipelines are handled using Flow lifecycle hooks. You apply the catch and retry operators alongside onCompletion to intercept exceptions and re-trigger emissions without breaking the coroutine stream pipeline.

Kotlin Flow integrates with callback-based APIs using callbackFlow. This builder bridges existing callback interfaces into a cold asynchronous stream, allowing you to suspend execution and safely emit values from external event producers.

Kotlin Flow streams and debounced transforms are tested using runTest and turbine. These testing frameworks allow you to control virtual time, collect emissions, and verify lifecycle hook behaviors or backpressure logic without asynchronous delays.