Welcome! It's an overlay for gentoo.
first of all, get a machine with gentoo. then:
emerge eselect-repository
eselect repository add ex_repo git https://github.com/Gerodote/ex_repo.git
eselect repository enable ex_repo
emaint sync -r ex_repo
then try emerge -av musikcube or equery u media-sound/musikcube::ex_repo. ( It works, but in GURU better )
also try emerge -av dev-libs/dbus-cxx and emerge -av dev-libs/cppgenerate