diff --git a/.github/workflows/build-iso.yml b/.github/workflows/build-iso.yml
index 0a6518f9..6640a137 100644
--- a/.github/workflows/build-iso.yml
+++ b/.github/workflows/build-iso.yml
@@ -44,8 +44,10 @@ jobs:
         with:
           script: nix build .#nixosConfigurations.${{ matrix.target }}.config.system.build.isoImage
 
-      - name: Delete nix store
-        run: sudo nix store gc && sudo nix store optimise
+      - name: Optimize nix store
+        uses: workflow/nix-shell-action@v3.2.1
+        with:
+          script: sudo nix store optimise
 
       - name: Upload iso
         uses: actions/upload-artifact@v3.1.2