Managing Interfaces for Sub-Graphs

Combining specifications of dataflow graphs includes receiving: a first dataflow graph specification that specifies two or more components connected by links representing flows of data, and a second dataflow graph specification that specifies at least one component, and at least one sub-graph interface. The sub-graph interface includes at least one flow junction representing a connection between: (1) a flow of data outside the sub-graph interface, and (2) a flow of data inside the sub-graph interface. The method includes processing information including the first dataflow graph specification and the second dataflow graph specification, to generate a combined dataflow graph specification, including: identifying an association between the sub-graph interface and the first dataflow graph specification, for at least a first flow junction, determining a direction associated with transferring a value of a descriptor, and transferring a value of a descriptor according to the determined direction.