Pull out common graphical module

hosts/common/default.nix

@@ -32,28 +32,6 @@
 
   virtualisation.docker.enable = true;
 
-  # Enable the X11 windowing system.
-  services.xserver = {
-    enable = true;
-    layout = "gb";
-
-    libinput = {
-      enable = true;
-      mouse = {
-        accelProfile = "flat";
-        accelSpeed = "1";
-      };
-    };
-
-    displayManager = {
-      gdm.enable = true;
-    };
-
-    windowManager.i3.enable = true;
-
-  };
-  
-
   # Enable sound.
   services.pipewire = {
 	enable = true;
@@ -84,7 +62,6 @@
     firefox
     gcc
     git
-    i3
     ripgrep
     wget
     zsh

hosts/common/graphical/default.nix

@@ -0,0 +1,27 @@
+{ config, pkgs, ...}:
+
+{
+  # Enable the X11 windowing system.
+  services.xserver = {
+    enable = true;
+    layout = "gb";
+
+    libinput = {
+      enable = true;
+      mouse = {
+        accelProfile = "flat";
+        accelSpeed = "1";
+      };
+    };
+
+    displayManager = {
+      gdm.enable = true;
+    };
+
+    windowManager.i3 = {
+      enable = true;
+      package = pkgs.i3-gaps;
+    };
+  };
+}
+