Add initial legacy configuration

nixos-modules/desktop/greeter.nix

@@ -0,0 +1,35 @@
+{
+  ...
+}:
+{
+
+  services.xserver.windowManager.i3.enable = false;
+
+  services.displayManager = {
+    defaultSession = "sway";
+  };
+
+  # Enable touchpad support.
+  services.libinput.enable = true;
+
+  services.xserver = {
+    enable = true;
+    desktopManager.xterm.enable = false;
+    displayManager = {
+      startx.enable = false;
+      lightdm.enable = false;
+      gdm = {
+        enable = true;
+        wayland = true;
+      };
+    };
+
+    # TODO: Extract i18n
+    xkb = {
+      layout = "ch,de";
+      options = "eurosign:e";
+    };
+
+    updateDbusEnvironment = true;
+  };
+}