The disclosure generally describes computer-implemented methods, software, and systems, including a method for automatically extending a service associated with data access. A request is received from a client, the request being for data associated with a first service. The first service is identified by a service identifier included in the request and defining a first behavior associated with the first service and use of the requested data. Using the service identifier, an extension service is identified that is associated with the first service. The identifying occurs automatically based on additional registry entries for the extension service, without modifying original registry entries for the first service, and without modifying a first service implementation associated with the first service. Data responsive to the received request is provided to the client. The data is provided according to a second behavior associated with the extension service.