diff --git a/services/nix-cache/nix.nix b/services/nix-cache/nix.nix
new file mode 100644
index 0000000..16809c7
--- /dev/null
+++ b/services/nix-cache/nix.nix
@@ -0,0 +1,7 @@
+{ lib, ... }:
+{
+  nix.settings.substituters = lib.mkForce [
+    "https://cache.nixos.org"
+    "https://cuda-maintainers.cachix.org"
+  ];
+}
diff --git a/system/nix.nix b/system/nix.nix
index 825ceb5..c754ddc 100644
--- a/system/nix.nix
+++ b/system/nix.nix
@@ -1,4 +1,4 @@
-{ ... }:
+{ lib, ... }:
 {
   nix = {
     gc = {
@@ -15,7 +15,7 @@
         "https://cache.nixos.org"
         "https://cuda-maintainers.cachix.org"
       ];
-      substituters = [
+      substituters = lib.mkDefault [
         "https://nix-cache.home.2rjus.net"
         "https://cache.nixos.org"
         "https://cuda-maintainers.cachix.org"