This is why Spack supports external packages. For any package, you can tell spack the prefix where it lives and build with that install prefix instead of a spac

This is why Spack supports external packages. For any package, you can tell spack the prefix where it lives and build with that install prefix instead of a spack-built version: https://spack.readthedocs.io/en/latest/build_settings.html#external-packages https://spack.readthedocs.io/en/latest/build_settings.html#e... People use this the tell Spack where the system cuda libs or system MPI are.