nix config to save some space

nixos/roles/default.nix

@@ -5,18 +5,11 @@
 }: {
   imports = [
     ./admins.nix
-    ./nix_keys.nix
+    ./nix.nix
     ./prometheusNodeExporter.nix
     ../modules/impermanence.nix
   ];
 
-  nix = {
-    extraOptions = ''
-      experimental-features = nix-command flakes
-      builders-use-substitutes = true
-    '';
-  };
-
   networking = {
     firewall = {
       # these shoud be default, but better make sure!

nixos/roles/nix.nix

@@ -0,0 +1,27 @@
+{
+  nix = {
+    settings = {
+      trusted-public-keys = [
+        "nerflap2-1:pDZCg0oo9PxNQxwVSQSvycw7WXTl53PGvVeZWvxuqJc="
+        "gonne.mathebau.de-1:FsXFyFiBFE/JxC9MCkt/WuiXjx5dkRI9RXj0FxOQrV0="
+      ];
+      experimental-features = [
+        "flakes"
+        "nix-command"
+      ];
+      auto-optimise-store = true;
+      fallback = true;
+      builders-use-substitutes = true;
+    };
+    gc = {
+      persistent = true;
+      dates = "weekly";
+      options = "-d";
+      randomizedDelaySec = "5h";
+    };
+    optimise = {
+      dates = [];
+      automatic = true;
+    };
+  };
+}

nixos/roles/nix_keys.nix

@@ -1,7 +0,0 @@
-{
-  imports = [];
-  nix.settings.trusted-public-keys = [
-    "nerflap2-1:pDZCg0oo9PxNQxwVSQSvycw7WXTl53PGvVeZWvxuqJc="
-    "gonne.mathebau.de-1:FsXFyFiBFE/JxC9MCkt/WuiXjx5dkRI9RXj0FxOQrV0="
-  ];
-}