diff --git a/environments/numlibs/spack.yaml b/environments/numlibs/spack.yaml
index c46d3fe..d3ae5a5 100644
--- a/environments/numlibs/spack.yaml
+++ b/environments/numlibs/spack.yaml
@@ -25,7 +25,7 @@ spack:
       - [$num_lib_types]
       - [$%compilers]
     - matrix:
-      - [parmetis]
+      - [parmetis, mumps +parmetis]
       - [$num_integer_types]
       - [$num_lib_types]
       - [$^mpis]