diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fe9d94248..5d681a0f4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -164,7 +164,7 @@ jobs:
     steps:
     - uses: actions/checkout@v6
     - name: Download installer tarball
-      uses: actions/download-artifact@v6
+      uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
       with:
         name: installer-${{matrix.os}}
         path: out
@@ -287,13 +287,21 @@ jobs:
         with:
           repository: NixOS/flake-regressions-data
           path: flake-regressions/tests
-      - uses: ./.github/actions/install-nix-action
+      - name: Download installer tarball
+        uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
         with:
-          dogfood: ${{ github.event_name == 'workflow_dispatch' && inputs.dogfood || github.event_name != 'workflow_dispatch' }}
-          extra_nix_config:
-            experimental-features = nix-command flakes
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-      - run: nix build -L --out-link ./new-nix && PATH=$(pwd)/new-nix/bin:$PATH MAX_FLAKES=25 flake-regressions/eval-all.sh
+          name: installer-linux
+          path: out
+      - name: Looking up the installer tarball URL
+        id: installer-tarball-url
+        run: |
+          echo "installer-url=file://$GITHUB_WORKSPACE/out" >> "$GITHUB_OUTPUT"
+      - uses: cachix/install-nix-action@4e002c8ec80594ecd40e759629461e26c8abed15 # v31.9.0
+        with:
+          install_url: ${{ format('{0}/install', steps.installer-tarball-url.outputs.installer-url) }}
+          install_options: ${{ format('--tarball-url-prefix {0}', steps.installer-tarball-url.outputs.installer-url) }}
+      - name: Run flake regressions tests
+        run: MAX_FLAKES=25 flake-regressions/eval-all.sh
 
   profile_build:
     needs: tests