How Quarkus Flow Talks to the World: The Messaging Architecture
A workflow engine that can’t talk to the outside world is just a fancy state machine running in isolation. The moment you need event-driven orchestration — pausing for a human approval, reacting to an external signal, emitting a domain event — you need a messaging bridge. And building one forces a decision: do you couple to Kafka? AMQP? Roll your own CloudEvent serialization and hope every connector plays nice? In previous posts, we explored why declarative workflows beat hand-rolled state machines and how Petri net semantics power parallel execution. This post goes one layer deeper: how Quarkus Flow actually moves events in and out of the engine, and why the answer is simpler than you might expect. ...