modules/theme: add custom theme module with wallpaper

flake.nix

@@ -7,13 +7,10 @@
 
       imports = [
         ./hosts
+        ./modules
       ];
 
-      perSystem = {
-        config,
-        pkgs,
-        ...
-      }: {
+      perSystem = {pkgs, ...}: {
         devShells.default = pkgs.mkShell {
           packages = [
             pkgs.alejandra

modules/default.nix

@@ -0,0 +1,5 @@
+{
+  flake.nixosModules = {
+    theme = import ./theme;
+  };
+}

modules/theme/default.nix

@@ -0,0 +1,15 @@
+{
+  lib,
+  config,
+  ...
+}: {
+  options.theme = {
+    wallpaper = lib.mkOption {
+      description = ''
+        Location of the wallpaper that will be used throughout the system.
+      '';
+      type = lib.types.path;
+      example = lib.literalExpression "./wallpaper.png";
+    };
+  };
+}