diff --git a/modules/_common/nixpkgs.nix b/modules/_common/nixpkgs.nix
index be3e744..b8299d3 100644
--- a/modules/_common/nixpkgs.nix
+++ b/modules/_common/nixpkgs.nix
@@ -5,12 +5,16 @@
     system = {
       stateVersion = "22.11";
       # enable auto updates
-      autoUpgrade.enable = true;
+      autoUpgrade = {
+        enable = true;
+        dates = "weekly";
+      };
     };
 
     nix.gc = {
       automatic = true;
-      dates = "00:30";
+      dates = "monthly";
+      options = "--delete-older-than 30d";
     };
   };
 }