V3 DDD Architecture

Identify the distinct responsibilities in the god object, then map each to a bounded context with its own entities, value objects, services, and repositories. Extract one domain at a time using a phased migration plan, wiring communication through domain events.

A microkernel architecture uses a minimal core kernel that loads domains and plugins at runtime through a registry and dependency container. Plugins declare dependencies on core domains and register their services with the kernel during initialization.

Bounded contexts communicate through domain events published to an event bus rather than direct method calls. Each context subscribes handlers to events from other domains, keeping coupling loose and contexts independently testable.

Clean architecture requires dependency inversion, which is typically implemented with dependency injection. Use cases and controllers receive repository and service interfaces through constructors, so the domain layer has no external dependencies.

DDD adds structural overhead that is not justified for small CRUD applications or prototypes with simple logic. It pays off when a codebase has complex business rules, multiple interacting concerns, or god objects that block testing and parallel development.