I have 2 small libraries (literally 1 class) designed as composer packages, they solve the same tasks, just by a different approach.
Without using interfaces or abstractions, I brought them to a uniform API, and my hands are itching to write an interface for them (this is the reverse). But writing the same interfaces in different repositories somehow doesn’t allow conscience.
How appropriate is it to single out an entire package for one interface (perhaps composer.json will weigh more than an interface file)? There are more beautiful solutions without merging repositories?