diff --git a/env/merlin/spack.yaml b/env/merlin/spack.yaml
index 47cad88..f47c53a 100644
--- a/env/merlin/spack.yaml
+++ b/env/merlin/spack.yaml
@@ -71,8 +71,8 @@ spack:
     - libtool
     - lua
     - m4
-    - mathematica
-    - matlab
+ #   - mathematica source needs to be provided
+ #   - matlab source needs to be provided
     - nasm
     - perl
     - nvhpc
@@ -87,7 +87,7 @@ spack:
     - filebench
     - ior
     - mdtest
-    - mxm
+#   - mxm not installable
     - nmap
     - patchelf
     - unison
@@ -97,7 +97,7 @@ spack:
     - coreutils
     - emacs
     - ffmpeg
-    - gams
+#   - gams source needs to be provided
     - gaussian
     - gettext
     - git