What is Domain-Driven Design

Domain-Driven Design is a software development approach to connect to an evolving complex model bounding into a core domain.

When we approach a complex system, we usually abstract it to a model that describes the different selected aspects of the system, and how we could use it to solve problems. When multiple models are in play, and the code base of different models is combined, the software becomes buggy, unreliable, and difficult to understand. It is often unclear in what context a model should not be applied. The domain is the sphere of knowledge that the users of our system understand, and what they use to interact with our software; they are the domain experts.

In DDD, we define the context within which a model applies; explicitly set boundaries in terms of team organization, usage within specific parts of the application, and physical manifestations such as code bases and database schemas, keeping the model strictly consistent within these bounds.