NestJS ports and adapters example

NestJS services tend to mix persistence, business rules and HTTP concerns in the same class, which makes them hard to test and to change.

Domain entities with no framework imports, incoming ports for commands and queries, outgoing repository ports, use case classes that depend only on ports, and MikroORM persistence entities with mappers on the adapter side. Shared building blocks such as an aggregate root and a base repository live in a shared-kernel library.

• The separation of domain, application, infrastructure and presentation layers carried into the MediOne, Dube, church and booking backends.

• Users, roles and role assignment as one bounded context
• Commands and queries with @nestjs/cqrs
• Repository ports with MikroORM adapters and mappers
• Shared-kernel library with aggregate root and base repository
• Typed configuration library