{ "": {"type": "export", "target": "slow", "flexible_config": ["RANGE"]}
, "slow":
  { "type": "generic"
  , "arguments_config": ["RANGE"]
  , "outs": ["out.txt"]
  , "cmds":
    [ "touch out.txt"
    , { "type": "join"
      , "$1":
        [ "for entry in "
        , {"type": "var", "name": "RANGE"}
        , " ; "
        , "do echo $entry >> out.txt ; "
        , "sleep 1 ; "
        , "done"
        ]
      }
    ]
  }
}