ark/locale/default.nix

{...}: {
  i18n = {
    defaultLocale = "en_US.UTF-8";
    supportedLocales = ["en_US.UTF-8/UTF-8" "tr_TR.UTF-8/UTF-8"];
  };
  time.timeZone = "Turkey";
  services.xserver.layout = "us";
  console.keyMap = "us";
}