By modern you mean using "docker", have an "io domain", and use node-js/go/rust? That seems to be the pattern these days. Take existing items, rewrite/repackage and io-ify it, maybe make it a SAAS product while at it.

ESBs historically required a domain-aware object model (when I saw them they were routed based upon rich types and terms like CORBA and RMI were still in vogue). This is more obvious when you look down the page for features in Apache Camel and they mention different data type support. Well, a workflow or orchestration engine doesn't need _any_ idea of your business layer data model to make decisions on where they need to be broadcast, but it's a convenience similar to listening to specific topics and segments in Kafka after querying a data broker service. Decoupling routing and representation of objects means that the bus is now dumb but the scheduler / router is now interchangeable. Which is how we can see so many possible competitors to Conductor and EBPM and all that now as shown in these comments.

Yes. The only difference from what I can tell is that each service/node on the bus is a VM/Container rather than a bespoke built machine.

dragonwriter below you says the opposite - based on a plane-level analysis. would be interested if that changes your mind.

The real answer is it depends on what you think what responsibilities exactly ESB or Workflow Orchestration should have. dragonwriter is of the reasonable opinion that ESBs focus should be a message plane. If your of my opinion, ESBs generally include some of the features found in workflow. devonkim is also right in that ESBs in general let the business data/process bleed into the rest of the stack, where as with workflow, its completely agnostic to the business data/process.

The most accurate answer would be from comparing various ESB products to Workflow Orchestration products, as every vendor/product will have slightly different opinions on where their responsibilities are.

fair enough. appreciate the thoughts!

> Are these just a modern incarnation of the enterprise service bus?

No, ESB is the messaging plane, workflow orchestration is a higher level service, on top of the messaging plane.