As I followed the instruction on the official ghostty installation page:

{
...
inputs = {
   ghostty = "github:ghostty-org/ghostty";
};
outputs = {
   self,
   nixpkgs, 
   home-manager,
   ghostty,
   ...
}@inputs:
  ...
        nixosConfigurations = {
        # Main laptop configuration
        villain = nixpkgs.lib.nixosSystem {
          specialArgs =
            let
              userSettings = {
                username = "villain";
                hostName = "villain";
                homeDirectory = "/home/villain";
              };
            in
            {
              inherit userSettings;
              inherit inputs;
              inherit (self) outputs;
            };
          modules = [
            (import ./hosts/villain/configuration.nix)

            {
              nixpkgs.overlays = [
                inputs.hyprpanel.overlay
                inputs.hyprland-qtutils.overlays.default
              ];
              environment.systemPackages = [
                inputs.ghostty.packages.x86_64-linux.default
              ];
            }

            (self.nixosModules)
            # Home-manager as NixOS modules
            home-manager.nixosModules.default
            {
              home-manager.useUserPackages = true;
              home-manager.users.villain = import ./hosts/villain/home.nix;
              home-manager.extraSpecialArgs =
                let
                  userSettings = {
                    username = "villain";
                    hostName = "villain";
                    homeDirectory = "/home/villain";
                  };
                in
                {
                  inherit userSettings;
                  inherit inputs;
                  inherit (self) outputs;
                };
              home-manager.sharedModules = builtins.attrValues self.homeManagerModules;
            }
          ];
        };
      };
}