Armed with this understanding, you try to infer a physical data model that can support the processes. The Data Layer The deepest level in the layered architecture, the data layer deals with data retrieval from its sources.
Every layer can exist without the layers above it, and requires the layers below it to function. The data access layer should provide an API to the application tier that exposes methods of managing the stored data without exposing or creating dependencies on the data storage mechanisms.
As with the separation of any tier, there are costs for implementation and often costs to performance in exchange for improved scalability and maintainability. Now, what about some good sleep? Out of a DDD analysis, any business domain is made of contexts and each context is shaped by logical contours.
Moving Away from a Technology Focus A decade ago, the typical. NET application. Expert developers can work very quickly with this approach, and junior developers can learn from it just as quickly.
This concept is called "aggregate" in the DDD jargon. If you have the database in mind, or if you feel more comfortable designing the database first, you can still do business layer as-usual, except that you code commands and queries separately in distinct classes and stacks.
But for the future of my career, I had to look deeper into software design and architecture.
Bounded context, instead, is the term that DDD uses to refer to areas of the domain that are better treated independently because they can be expressed via their own ubiquitous language.
Multiple presentations could be separate pages in a web app, having a web app plus mobile native apps, an API for scripting purposes, or even an old fashioned command line interface.