add: backlight.nix

modules/system/default.nix

@@ -1,6 +1,7 @@
 {pkgs, ...}: {
   imports = [
     ../../system/time.nix
+    ../../system/backlight.nix
     ../../system/boot.nix
     ../../system/amd.nix
     ../../system/hardware.nix

system/backlight.nix

@@ -0,0 +1,9 @@
+{
+  pkgs,
+  myConfig,
+  ...
+}: {
+  hardware.i2c.enable = true;
+  environment.systemPackages = with pkgs; [ddcutil];
+  users.users.${myConfig.nixos.username}.extraGroups = ["i2c"];
+}