use modules

modules/nix-settings.nix

@@ -0,0 +1,25 @@
+{
+  pkgs,
+  lib,
+  config,
+  ...
+}: {
+  # Allow unfree packages
+  nixpkgs.config.allowUnfree = true; # TODO: replace this with allowUnfreePredicate
+
+  # enable nix flakes
+  nix.settings.experimental-features = ["nix-command" "flakes"];
+
+  nix.settings.trusted-users = ["root" "osbm"];
+
+  nix.gc = {
+    automatic = true;
+    dates = "weekly";
+    options = "--delete-older-than 30d";
+  };
+
+  nix.nixPath = ["nixpkgs=${pkgs.path}"];
+
+  # disable the database error TODO add nix-index search
+  programs.command-not-found.enable = false;
+}