diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 2a674a8cb58ff4c364b472641b538630117a5ffa..57eb234d7d8a67b7cc6907ff8bf4ef206f0dfdfa 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -45,6 +45,9 @@     - name: Install nix
       uses: cachix/install-nix-action@v16
       with:
         nix_path: "${{ matrix.nixPath }}"
+        # nix 2.6 breaks restrict-eval, when using the NIX_PATH
+        # see https://github.com/NixOS/nix/issues/5980
+        install_url: https://releases.nixos.org/nix/nix-2.5.1/install
         extra_nix_config: |
           experimental-features = nix-command flakes
           access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}