1. A method for implementing a hierarchical software design formed of a plurality of decomposition levels each comprising a control, at least one process, wherein each decomposable process has a corresponding sub-graph, and where each non-decomposable processes has associated code that implements functionality of the process, comprising: translating one of the decomposition levels directly into an executable finite state machine having: a plurality of states including one state corresponding to the control and additional states each respectively corresponding to one of the non-decomposable processes and formed of executable code associated with the non-decomposable process; and state transitions formed of interpreted code that represents control flow between the control state and the additional states defined within sub-graphs of the decomposable processes; and interpreting the state transitions to invoke execution of the states to implement the hierarchical software design.