Implementing Domain-Driven Design

Hexagonal or Ports and Adapters

With the Hexagonal Architecture² Alistair Cockburn codified a style to produce symmetry [Cockburn]. It advances this goal by allowing many disparate clients to interact with the system on equal footing. Need a new client? Not a problem. Just add an Adapter to transform any given client’s input into that understood by the internal application’s API. At the same time, output mechanisms employed by the system, such as graphics, persistence, and messaging, may also be diverse and swappable. That’s possible because an Adapter is created to transform application results into a form accepted by a specific output mechanism.

2. We refer to this architecture by the name Hexagonal, even though its name seems to have changed ...