diff --git a/.github/workflows/nix-ci.yml b/.github/workflows/nix-ci.yml
index 2f1953f299..988593e4c7 100644
--- a/.github/workflows/nix-ci.yml
+++ b/.github/workflows/nix-ci.yml
@@ -33,6 +33,8 @@ jobs:
       - name: Install Nix
         uses: cachix/install-nix-action@v15
         with:
+          # https://github.com/NixOS/nix/issues/6572
+          install_url: https://releases.nixos.org/nix/nix-2.7.0/install
           extra_nix_config: |
             extra-sandbox-paths = /nix/var/cache/ccache
             substituters = file://${{ github.workspace }}/nix-store-cache-copy?priority=10&trusted=true https://cache.nixos.org