Composition root

UseCases is the only type that constructs NoteRepositoryImpl.

clean-architectureserverpodhybrid

lib/src/app/ wires the shared impl into the use case the feature endpoint calls. The endpoint folder does not get its own composition root.

Repositories holds the store and returns NoteRepositoryImpl(store). UseCases holds the repositories, the clock, and the id generator, and returns a SaveNoteUseCase or a ListNotesUseCase.

dart

SaveNoteUseCase saveNote() => SaveNoteUseCase(
  _repositories.noteRepository(),
  clock: _clock,
  ids: _ids,
);

The endpoint calls useCases.saveNote(). A unit test does not. It constructs SaveNoteUseCase with a fake repository, which is why the use case depends on the port.

app/ has no title check and no SQL. Those stay in Note.create and the repository impl. The files are lib/src/app/use_cases.dart and lib/src/app/repositories.dart.

Next: Tests.