let wget_untar
      ~host ~(run_program : Machine.Make_fun.t)
      ~destination_folder ~tar_contains url =
    let open KEDSL in
    let zip_flags =
      let is_gz = Filename.check_suffix url ".gz" in
      let is_bzip = Filename.check_suffix url ".bz2" in
      if is_gz then "z" else if is_bzip then "j" else ""
    in
    let tar_filename = (destination_folder ^ ".tar") in
    let name = "untar-" ^ tar_filename in
    let wgot = wget ~host ~run_program url tar_filename in
    let file_in_tar = (destination_folder // tar_contains) in
    workflow_node
      (single_file file_in_tar ~host)
      ~edges:[
        depends_on (wgot);
        on_failure_activate (Remove.path_on_host ~host destination_folder);
      ]
      ~name
      ~make:(
        run_program ~name
          ~requirements:(Machine.Make_fun.stream_processor [])
          Program.(
            exec ["mkdir"; "-p"; destination_folder]
            && shf "tar -x%s -f %s -C %s"
              zip_flags
              (Filename.quote wgot#product#path)
              (Filename.quote destination_folder)))