diff --git a/nix-os/core.nix b/nix-os/core.nix
index a65ffe1..8d8c9b3 100644
--- a/nix-os/core.nix
+++ b/nix-os/core.nix
@@ -22,9 +22,12 @@
     nixpkgs.config.allowUnfree = true;
     nix = {
       channel.enable = false;
-      settings.experimental-features = [
-        "no-url-literals"
-      ];
+      settings = {
+        auto-optimise-store = true;
+        experimental-features = [
+          "no-url-literals"
+        ];
+      };
       nixPath = [
         "nixpkgs=${pkgs.selfExpr { useConfig = false; }}"
         "systemNixpkgs=${pkgs.selfExpr { useConfig = true; name = "systemNixpkgs-self"; }}"