Yes, I meant the impl.

> If I see a test dependency I usually expect that I won't need that at runtime.

I see what you mean. Maybe `runtime` would actually be better?

To me, `provided` signals that classes from this dependency may be referenced in code (it is just expected to be provided by the environment at runtime). I think that's not really what we want, because we don't expect this particular impl to be used at runtime, but just any impl.