1. A method comprising: an application sending to a container a data object specifying a high-level function provided by a system external to the application; the container receiving the data object specifying the high-level function; the container accessing metadata corresponding to the high-level function call, wherein the metadata describes the high-level function of the external system; the container performing one or more transformations on the data object specifying the high-level function in accordance with the metadata to produce a data object including information for driving a connector to the external system to make a plurality of low-level calls to the external system to perform the high-level function; the container executing the data object including the information for driving the connector to the external system to drive the connector to make the plurality of low-level calls to the external system; and the external system executing a plurality of low-level functions as specified by the plurality of low-level calls received from the connector, wherein said executing the plurality of low-level functions performs the high-level function of the external system specified by the high-level function call.