It's nothing to do with concurrency - the event bus pattern will alleviate much of the pain around event-driven programming (the FSM's you were referring to) an

It's nothing to do with concurrency - the event bus pattern will alleviate much of the pain around event-driven programming (the FSM's you were referring to) and decouple the event handling machines. In my experience, moving to an event bus model makes event driven programming very manageable. If the event bus has executors (which it could in v8), it will be parallel to boot.