1. A computing system comprising: a processor configured to execute software to manage a first plurality of objects; an interface, wherein the interface is configured to receive a run-time extension from a client processing system, the run-time extension is communicated via a remote procedure call from the client processing system; the client processing system manages a second plurality of objects that correspond to the first plurality of objects; the second plurality of objects comprises a first object and a second object on the client processing system; the first is a member of an application class; the second object is a member of the application class; the run-time extension modifies, using a script coupled to the first object when the first object is instantiated, the first object on the client processing system without modifying the second object on the client processing system; and a compiler, wherein the compiler is configured to compile the run-time extension on the processor to modify a base behavior of the class.