This guide introduces the core concepts and provides an overview of the building blocks of Apache Isis applications.
It next describes the basics of the Apache Isis' programming model: domain entities and services, object members, UI layout and hints, business rules and drop downs and defaults. This includes a discussion on the basic CRUD operations.
It then moves on to discuss some slightly more advanced areas of the programming model: meta-annotations, view models and mixins. These all allow you to develop more sophisticated applications, while remaining maintainable and elegant. There is also a discussion on how to structure your application using modules.
Finally the Beyond the Basics tackles some more advanced topics.