Create catppuccin-sddm package.

nixos/configuration.nix

@@ -78,17 +78,14 @@
   services.xserver.displayManager.sddm = {
     enable = true;
     wayland.enable = true;
-    theme = "catppuccin-sddm-corners";
+    theme = "catppuccin-frappe";
     # Fix keyboard showing up unnecesarilly
     settings = { General = { InputMethod = ""; }; };
   };
 
-  # Set default sddm session to plasma wayland
-  services.xserver.displayManager.defaultSession = "plasmawayland";
-
   # Setup plasma with excluding a couple unnecesarry packages
-  services.xserver.desktopManager.plasma5.enable = true;
-  environment.plasma5.excludePackages = with pkgs.libsForQt5; [
+  services.desktopManager.plasma6.enable = true;
+  environment.plasma6.excludePackages = with pkgs.libsForQt5; [
     plasma-browser-integration
     konsole
     oxygen
@@ -160,6 +157,7 @@
     xfsprogs
     (catppuccin-kde.override { winDecStyles = [ "classic" "modern" ]; })
     catppuccin-sddm-corners
+    (callPackage ./modules/catppuccin-sddm.nix { inherit pkgs; })
   ];
 
   # firewall settings

nixos/modules/catppuccin-sddm.nix

@@ -0,0 +1,20 @@
+{ pkgs }:
+
+pkgs.stdenv.mkDerivation {
+  pname = "catppuccin-sddm";
+  version = "1a58b5c";
+
+  src = pkgs.fetchFromGitHub {
+    owner = "catppuccin";
+    repo = "sddm";
+    rev = "1a58b5c2d898a70c22e4d9462039111f5613a7c0";
+    hash = "sha256-cZuNQDXdWiE2eCf/bdGFYKM5SXrENxJere83SI47ol4=";
+  };
+    
+  dontBuild = true;
+
+  installPhase = ''
+    mkdir -p $out/share/sddm/themes
+    cp -r ./src/* $out/share/sddm/themes
+  '';
+}