Separation of Concerns The main objective of DDD is to create separation of concern to keep the system stable. The term Separation of Concerns means in computer programming to use different mechanisms to separate things that do not have with each other to do. The most known is might be the MVC pattern with separates Models, Views and Controllers. Here we are not talking about MVC: We are talking about DDD but of course these patterns can be combined to some extent. The separation takes place in two different directions in DDD: Bounded contexts that I will return to in a later post. DDD people often talk about something called a hexagonal design. As I never have found any good explanation of why the authors use the hexagon symbol I do not use it, but it might be good to know that the term exists. The hexagonal design is intended to divide up the application in the parts and control how they communicate with each other. Sometimes called the pattern also is called Ports and ...