diff --git a/hosts/hydrogen/system/nix/default.nix b/hosts/hydrogen/system/nix/default.nix
new file mode 100644
index 0000000..4626f4b
--- /dev/null
+++ b/hosts/hydrogen/system/nix/default.nix
@@ -0,0 +1,11 @@
+{ ... }: {
+  # optimizations
+  nix.settings.auto-optimise-store = true;
+
+  # garbage collection
+  nix.gc = {
+    automatic = true;
+    dates = "weekly";
+    options = "--delete-older-than 30d";
+  };
+}