1. A method for providing federated functionality within a data processing system, the method comprising: receiving a first request at a first computing system for requested federation services from an identity provider, wherein the first request is made by a first requestor; initializing an instance of an application to provide the requested federation services for the first requestor, the instance of the application resulting in a first specialized runtime which is specialized according to configuration data of a federation relationship of the first requestor with the identity provider, wherein the configuration data is dynamically retrieved during initialization of the runtime; and providing the requested federation services using the specialized runtime, wherein the identity provider provides federation services for a plurality of requestors, further comprising: initializing a plurality of specialized runtimes which provide requested federation services for the requestors according to configuration data of respective federation relationships of the requestors with the identity provider, wherein the configuration data is dynamically retrieved during initialization of the runtimes; and providing the requested federation services to each requestor by routing requests to an appropriate specialized runtime according to a requestor identity and a federation relationship.