need to do it after we did the environment

.github/actions/dependencies/action.yml

@@ -35,17 +35,6 @@ runs:
       run: |
         CI/dependencies/setup_spack.sh
 
-    - name: Compress spack directory for caching
-      shell: bash
-      run: |
-        tar cf spack.tar spack/
-        zstd -T0 -19 spack.tar -o spack.tar.zst
-
-    - uses: actions/cache/save@v4
-      with:
-        path: spack.tar.zst
-        key: spack-clone
-
     - name: Prerequisites
       if: startsWith(runner.os, 'macos')
       shell: bash
@@ -65,3 +54,14 @@ runs:
           echo "Without compiler"
           CI/dependencies/setup.sh
         fi
+
+    - name: Compress spack directory for caching
+      shell: bash
+      run: |
+        tar --exclude='opt' cf spack.tar spack/
+        zstd -T0 -19 spack.tar -o spack.tar.zst
+
+    - uses: actions/cache/save@v4
+      with:
+        path: spack.tar.zst
+        key: spack-clone

CI/dependencies/setup.sh

@@ -99,7 +99,25 @@ mkdir -p ${destination}
 
 
 start_section "Install spack if not already installed"
-source "${SCRIPT_DIR}/install_spack.sh"
+if ! command -v spack &> /dev/null; then
+    if [ ! -d "spack" ]; then
+        echo "Cloning spack"
+        git clone -c feature.manyFiles=true https://github.com/spack/spack.git
+        pushd spack > /dev/null
+        git config user.name github-actions[bot]
+        git config user.email 41898282+github-actions[bot]@users.noreply.github.com
+        # Apply patch for spack improvements
+        curl https://patch-diff.githubusercontent.com/raw/spack/spack/pull/47370.patch | git am
+        popd > /dev/null
+    else
+        echo "Updating spack"
+        pushd spack > /dev/null
+        git pull --rebase
+        popd > /dev/null
+    fi
+
+    source "$(pwd)/spack/share/spack/setup-env.sh"
+fi
 end_section
 
 if [ -n "${CI:-}" ]; then