A computer implemented method, computer program product, and a data processing system access a version of shared assembly in a componentized environment, wherein multiple versions of the shared assembly exist concurrently in a single process, and wherein each version of the shared assembly comprises an assembly stub and an assembly implementation. A call to an assembly stub of the shared assembly is received. The call is then forwarded from the assembly stub to an identified assembly implementation using a proxy pointer. A function table structure is then retuned from the identified assembly implementation, wherein the function table structure contains implementation symbols from the identified assembly implementation.