The three parts I call the Persistent-object partition, in red, the Session-object partition, in yellow, and the Session-object Editor partition, in green.

The user interface, including the projectors that respond to user events, is all in the green Editor partition. No coding is required to build these editors. As you have seen, some domain information is exposed in the dialogs used to define what field of a record is displayed.

The yellow Session-object partition is where  domain experts negotiate their access to domain-object services with developers. As you have seen, the services are exposed in dialogs that project parameters of components such as New Record and Select Field. A negotiation between developers and domain experts around services exposed in the yellow part helps developers define these services, which are largely implemented by developers in the red part.

There is another component in the yellow part, called Message, which I haven’t used here and I’ll show next.