refactor(modules/system): move system config to a module

lib/default.nix

@@ -0,0 +1,7 @@
+{ lib, ... }:
+{
+  mkStrOption = lib.mkOption {
+    type = lib.types.str;
+    default = "";
+  };
+}

modules/nixos/hardware/default.nix

@@ -8,15 +8,9 @@
   options.hardware = {
     drives.btrfs = {
       enable = lib.mkEnableOption "";
-      drive = lib.mkOption {
-        type = lib.types.str;
-        default = "";
-      }; 
+      drive = lib.pantheon.mkStrOption;
       ephemeralRoot = lib.mkEnableOption "";
     };
-    gpu = lib.mkOption {
-      type = lib.types.str;
-        default = "";
-    };
+    gpu = lib.pantheon.mkStrOption;
   };
 }

modules/nixos/system/default.nix

@@ -0,0 +1,16 @@
+{ config, lib, ...}:
+{
+  imports = [
+    ./users.nix
+    ./localisation.nix
+    ./nix-config.nix
+  ];
+
+  options.system = {
+   mainUser = lib.pantheon.mkStrOption;
+  };
+
+  config = {
+    system.stateVersion = "25.05"; # Did you read the comment?
+  };
+}

modules/nixos/system/localisation.nix

@@ -0,0 +1,9 @@
+{ config, lib, ... }:
+{
+  config = lib.mkMerge [
+    {
+	  time.timeZone = "Asia/Singapore";
+	  i18n.defaultLocale = "en_US.UTF-8";
+    }
+  ];
+}

modules/nixos/system/nix-config.nix

@@ -0,0 +1,6 @@
+{ config, lib, ... }:
+{
+  config = {
+    nix.settings.experimental-features = ["nix-command" "flakes"];
+  };
+}

modules/nixos/system/users.nix

@@ -0,0 +1,18 @@
+{ config, lib, pkgs, ... }:
+{
+  config = lib.mkMerge [
+    {
+      users.users."${config.system.mainUser}" = {
+        isNormalUser = true;
+        initialPassword = "1";
+        extraGroups = [ 
+	  "wheel" 
+	];
+        packages = with pkgs; [
+          git
+          neovim
+        ];
+      };
+    }
+  ];
+}

systems/x86_64-linux/nemesis/default.nix

@@ -1,5 +1,6 @@
 { config, lib, pkgs, ... }:
 {
+  system.mainUser = "rafiq";
   hardware.drives.btrfs = {
     enable = true;
     drive = "/dev/disk/by-id/nvme-CT2000P3SSD8_2325E6E77434";
@@ -7,32 +8,23 @@
   };
   hardware.gpu = "nvidia";
 
+
+  hardware.cpu.amd.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
   boot.initrd.availableKernelModules = [ "nvme" "xhci_pci" "ahci" "usbhid" "usb_storage" "sd_mod" ];
   boot.initrd.kernelModules = [ "dm-snapshot" ];
   boot.kernelModules = [ "kvm-amd" ];
   boot.loader.systemd-boot.enable = true;
   boot.loader.efi.canTouchEfiVariables = true;
+
   networking.useDHCP = lib.mkDefault true;
-  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
-  hardware.cpu.amd.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;
   networking.hostName = "nemesis"; # Define your hostname.
   networking.networkmanager.enable = true;  # Easiest to use and most distros use this by default.
-  time.timeZone = "Asia/Singapore";
-  i18n.defaultLocale = "en_US.UTF-8";
+
   services.pipewire = {
     enable = true;
     pulse.enable = true;
   };
-  users.users.rafiq = {
-    isNormalUser = true;
-    initialPassword = "1";
-    extraGroups = [ "wheel" ]; # Enable ‘sudo’ for the user.
-    packages = with pkgs; [
-      git
-      neovim
-    ];
-  };
-  nix.settings.experimental-features = ["nix-command" "flakes"];
-  system.stateVersion = "25.05"; # Did you read the comment?
+
 }