`rpmbuild` has had a `--build-in-place` feature for a number of years (since rpm 4.13.0). With that, you don't need a source, or a tarball, and the actions of %

`rpmbuild` has had a `--build-in-place` feature for a number of years (since rpm 4.13.0). With that, you don't need a source, or a tarball, and the actions of %prep, %build, and %install are done from the current working directory. This is similar to what have been able to do to make debs with dpkg-deb.