1. In a system in which reconfigurable compute engines have input and output pins and are interconnected to perform a predetermined function and in which each of said reconfigurable compute engine includes an application layer and a physical layer, an interconnect fabric, comprising: a reconfigurable interconnect layer between said application layer and said physical layer, the interconnect layer being reprogrammable to provide a different switching function to set the connections for the physical layer for defining a new function for the compute engine by redefining interconnects without reconfiguring the physical layer and thus without affecting the application layer and regardless of what is happening in the application layer.