1. A computer program product, tangibly embodied in an information carrier, the computer program product comprising instructions operable to cause data processing apparatus to: receive a specified name; retrieve one or more resources from a database, and for each resource, one or more attributes associated with the resource, wherein each resource comprises executable instruction code, and wherein the attributes comprise a name that matches the specified name; select one of the retrieved resources based on the attributes associated with each resource; and load the selected resource into a runtime system.