Previously compiler passes were relying on relative paths to access schema definitions generated in app/config/graphql/ezplatform directory. This wasn't really working when symlinks were used during development. I think symlinks are still the best method when working with multiple packages so I couldn't align on my side to overcome this issue.
I have a proposal to move schema directories from constants to container parameters. It's more natural to me to store such information in the container which makes it accessible in services, extensions and compiler passes.