diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 921060ad..8bb5c487 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -13,6 +13,10 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - uses: DeterminateSystems/nix-installer-action@main
+        with:
+          extra-conf: |
+            trusted-public-keys = cache.garnix.io:CTFPyKSLcx5RMJKfLo5EEPUObbA78b0YQ2DTCJXqr9g= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
+            substituters = https://cache.garnix.io?priority=40 https://cache.nixos.org/
       - uses: DeterminateSystems/magic-nix-cache-action@main
       - uses: yaxitech/nix-install-pkgs-action@v3
         with: