Classic BLoC vs BlocSignal: How Flutter handles rapid .add() event calls

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Flutter developers often worry that calling .add() multiple times in quick succession may cause events to overwrite each other before the UI can respond. In Classic BLoC, events are queued through Dart Streams, with each handler executing sequentially and the UI updating only on the next Flutter render frame. BlocSignal follows the same .add() and emit() API but replaces Streams with Signals, making handler execution synchronous so bloc.state reflects the new state immediately after .add() returns. In both implementations, no events are lost even when thousands are dispatched rapidly, because Flutter's markNeedsBuild() simply flags a widget as dirty once and rebuilds it once per frame using the latest state. The key distinction between the two approaches is propagation timing, not event reliability.

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