System and method for programmatically determining routing with signal modifications in a measurement system to perform a measurement task. Information is received specifying a route from a source terminal to a destination terminal in the measurement system, including signal modification requirements and a graph of possible routes in the measurement system. A current signal modification of the route is determined and used with the signal modification requirements to determine desired changes in the signal modification of the route. The legs of the route are walked in the graph, and one or more legs are replaced with respective alternative legs, each of which includes at least a portion of the desired changes in the signal modification, thereby generating a modified route which satisfies the signal modification requirements for the route, where the modified route is usable to route signals in performing the measurement task. The modified route is then stored.