Summary on Use Cases/Application Services

Use cases are infrastructure-layer concern agnostic. If we design them as little modules that as long as we can provide the correct inputs, they'll know how to execute the features of our system, they can stay agnostic to what API style executes them.

You'll notice that in the DDDForum codebase, a single useCase/ folder has several files in it. Each folder has the Controller, the DTO, the UseCaseErrors, and the Use Case

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