Arquitectura Hexagonal (Backend)

Hexagonal architecture isolates core domain logic from infrastructure details like databases, enabling unit testing of business rules without complex framework mocks. This decoupling allows applications to be driven by various inputs independently of runtime technologies.

Decouple domain logic from NestJS by structuring projects into distinct domain, application, and infrastructure layers using the Ports and Adapters pattern. Interfaces define ports for inputs, while concrete implementations act as adapters, keeping business rules technology agnostic.

Structure a NestJS backend using clean architecture by dividing it into domain, application, and infrastructure layers. Use interfaces for ports and concrete implementations for adapters to isolate the core domain, ensuring business logic is independent of databases and APIs.

Yes, you can swap databases without rewriting business logic by using hexagonal architecture. This approach isolates core domain rules from infrastructure, treating databases as interchangeable adapters connected through defined ports, ensuring technology agnosticism.

You should avoid hexagonal architecture for simple backend services where managing distinct domain, application, and infrastructure layers adds unnecessary complexity. It is best suited for complex systems requiring high decoupling, strict separation of concerns, and technology agnosticism.