I extend this to explicitly have an adaptor in the middle: app > depends on > app interface service > implements > api adaptor > composes (api >

I extend this to explicitly have an adaptor in the middle: app > depends on > app interface service > implements > api adaptor > composes (api >> app interface) That way the app doesn't need to know about the API, nor the API about the app. The wiring up the two are managed by the adaptor which is free to be implemented on the client/app side or vendor/service side.