system/nix: add some nix configurations

enable automatic garbage collection and add wheel users to trusted nix
users.

Signed-off-by: Kenny Ballou <kballou@devnulllabs.io>

1 files changed, 16 insertions, 0 deletions

diff --git a/system/nix.nix b/system/nix.nix
new file mode 100644
index 0000000..7d8971d
--- /dev/null
+++ b/system/nix.nix
@@ -0,0 +1,16 @@
+{ config, pkgs, ... }:
+{
+  nix = {
+    trustedUsers = [ "@wheel" ];
+    daemonIONiceLevel = 3;
+    daemonNiceLevel = 17;
+    gc = {
+      automatic = true;
+      options = "--delete-older-than 14d";
+    };
+    optimise = {
+      automatic = true;
+      dates = [ "Sun 03:45" ];
+    };
+  };
+}