diff --git a/configuration.nix b/configuration.nix
index e9cc3ef..e2aff79 100644
--- a/configuration.nix
+++ b/configuration.nix
@@ -52,7 +52,11 @@ in {
   system.autoUpgrade.enable = true;
   system.stateVersion = "18.09";
 
-  nix.gc.automatic = true;
-  nix.gc.dates = "weekly";
-  nix.gc.options = "--delete-older-than 30d";
+  nix = {
+    optimise.automatic = true;
+    gc = {
+      automatic = true;
+      options = "--delete-older-than 7d";
+    };
+  };
 }