{pkgs, ...}: {
  programs = {
    bash.interactiveShellInit = ''
      if [[ $(${pkgs.procps}/bin/ps --no-header --pid=$PPID --format=comm) != "fish" && -z ''${BASH_EXECUTION_STRING} ]]; then
        shopt -q login_shell && LOGIN_OPTION='--login' || LOGIN_OPTION=""
        exec ${pkgs.fish}/bin/fish $LOGIN_OPTION
      fi
    '';
    fish.enable = true;
  };
}
