diff --git a/environments/hlrs/spack.yaml b/environments/hlrs/spack.yaml
index 5c2ca52..dde7206 100644
--- a/environments/hlrs/spack.yaml
+++ b/environments/hlrs/spack.yaml
@@ -4,9 +4,9 @@ spack:
     - core_compiler: [gcc@7.5]
     - compilers: [gcc@13.2, cce@18.0]
     - mpis: [cray-mpich@8.1.30]
-#  packages:
-#    all:
-#      compiler: [gcc@13.2, cce@18.0]
+  packages:
+    all:
+      prefer: ['%gcc@7.5']
   # add package specs to the `specs` list
   specs:
     - matrix:    # modules for low-level tools