diff --git a/system/nix.nix b/system/nix.nix
index 640ce32..825ceb5 100644
--- a/system/nix.nix
+++ b/system/nix.nix
@@ -1,19 +1,30 @@
-{ pkgs, ... }:
+{ ... }:
 {
+  nix = {
+    gc = {
+      automatic = true;
+    };
 
-  nix.settings.trusted-substituters = [
-    "https://nix-cache.home.2rjus.net"
-    "https://cache.nixos.org"
-    "https://cuda-maintainers.cachix.org"
-  ];
-  nix.settings.substituters = [
-    "https://nix-cache.home.2rjus.net"
-    "https://cache.nixos.org"
-    "https://cuda-maintainers.cachix.org"
-  ];
-  nix.settings.trusted-public-keys = [
-    "nix-cache.home.2rjus.net-1:2kowZOG6pvhoK4AHVO3alBlvcghH20wchzoR0V86UWI="
-    "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
-    "cuda-maintainers.cachix.org-1:0dq3bujKpuEPMCX6U4WylrUDZ9JyUG0VpVZa7CNfq5E="
-  ];
+    optimise = {
+      automatic = true;
+    };
+
+    settings = {
+      trusted-substituters = [
+        "https://nix-cache.home.2rjus.net"
+        "https://cache.nixos.org"
+        "https://cuda-maintainers.cachix.org"
+      ];
+      substituters = [
+        "https://nix-cache.home.2rjus.net"
+        "https://cache.nixos.org"
+        "https://cuda-maintainers.cachix.org"
+      ];
+      trusted-public-keys = [
+        "nix-cache.home.2rjus.net-1:2kowZOG6pvhoK4AHVO3alBlvcghH20wchzoR0V86UWI="
+        "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
+        "cuda-maintainers.cachix.org-1:0dq3bujKpuEPMCX6U4WylrUDZ9JyUG0VpVZa7CNfq5E="
+      ];
+    };
+  };
 }