I'm seeing issues building with spack with the following line in package.py
https://github.com/LLNL/UMT/blob/a110b15f7bb77237b31d2edb76f1192c235a1069/spack/package.py#L168
I think this should be if "+find_mpi" in self.spec or there should be something like spec = self.spec as in other functions.