Flow vs Sequence — what’s the key difference?

Deep dive

`Sequence` is pull-based and synchronous: operations run when you iterate, on the current thread.

`Flow` is also cold (doesn’t run until collected), but it’s suspendable/cancellable and integrates with coroutines. It can represent async sources (DB, network, UI events) and supports operators with proper cancellation.

Practical guidance

• Use `Sequence` for CPU-bound lazy transforms on in-memory data.
• Use `Flow` for async streams and when you need cancellation/backpressure-ish behavior.

Common pitfalls

• Expecting Flow to run on a background thread automatically (use `flowOn` / proper dispatcher).
• Doing blocking IO inside Flow without switching context.