Nice to see you here Peter,
I am hoping, with the new capabilities with the Agentic Orchestration layer that having an Orchestration layer, which could also be called the business logic layer, will become alot more mainstream, with performers dedicated to Ui tasks only and so perhaps being considered the ‘Ui layer’.
From my understanding of separation in the world of front end design, a ‘Data layer’ per say doesnt quite match up properly as alot of the time the data isnt persistent enough to warrant such a architecture and it can mostly be handled in the Orchestration layer.
I think Libraries also play a part, but are perhaps not clear as a layer, but this is where I like to define all the actual Ui interactions, with them being wrapped into re-usable activities which can then be leveraged in a performer.
Its largely a semantic choice, and the ‘layers’ should not conform to the same standards as in front end design, your notes on simply splitting workflows into layers could be considered to be simply following SOLID principles, but they could be also argued as a type of ‘workflow layers’ whilst I was thinking more in terms of projects.