nixos-config/modules/core/xserver.nix

{ pkgs, ... }: 
{
  services.xserver = {
    enable = true;
    layout = "us";
    displayManager.autoLogin = {
      enable = true;
      user = "frostphoenix";
    };
    libinput = {
      enable = true;
      mouse = {
        # accelProfile = "flat";
      };
    };
  };
}