diff --git a/env/merlin/spack.yaml b/env/merlin/spack.yaml
index 03bf6aa..8b68cb2 100644
--- a/env/merlin/spack.yaml
+++ b/env/merlin/spack.yaml
@@ -13,29 +13,25 @@ spack:
         - slurm
     - Compiler_pckgs: &Compiler_pckgs
         # E.G: removing atlas from testing, since it taking way too much time. Installation working though.
-        # - atlas%gcc
-        # - clapack%gcc
-        - boost%clang
-        - boost%gcc
-        - boost%nvhpc
-        - boost%oneapi
-        - clhep%gcc
-        - eigen%gcc
-        - geant4%gcc
-        - googletest%gcc
-        - gsl%gcc
-        - intel-oneapi-mpi%oneapi
-        - kokkos%gcc
-        - libint%oneapi tune=cp2k-lmax-6 ^gmp%oneapi
-        - libxc%oneapi
-        - libxsmm%oneapi
-        - mpich%gcc netmod=ucx
-        - openblas%gcc threads=none
-        - openblas%gcc threads=openmp
-        - openmpi%gcc
-        - root%gcc ~tbb~x
-        - superlu%gcc
-        - vtk%gcc
+        # - atlas
+        # - clapack
+        - boost
+        - clhep
+        - eigen
+        - geant4
+        - googletest
+        - gsl
+        - intel-oneapi-mpi
+        - kokkos
+        - libint
+        - libxc
+        - libxsmm
+        - mpich
+        - openblas
+        - openmpi
+        - root
+        - superlu
+        - vtk
     - Cuda_pckgs: &Cuda_pckgs
         - cuda
     - EM_pckgs: &EM_pckgs
@@ -546,7 +542,22 @@ spack:
         - PKG_CONFIG_PATH
 #<<<
   specs:
-    - $Compiler_pckgs
+    - matrix:
+      - [alps, geant4, gromacs, h5hut+mpi, lammps, r, superlu, visit, vtk, root ~tbb
+          ~x]
+      - ['%gcc']
+      - [^openmpi]
+      - [^openblas]
+    - matrix:
+      - [cp2k]
+      - ['%oneapi']
+      - [^intel-oneapi-mpi]
+      - [^intel-oneapi-mkl]
+    - matrix:
+      - [relion +cuda]
+      - ['%nvhpc']
+      - [^openmpi]
+      - [^openblas]
   view:
     Batchsystem:
       link: all