An endpoint emulator of an endpoint service in a network computer arrangement which generates emulator service classes according to service descriptor files, the classes being Web Services Description Language descriptors contained in a web container, provides an emulator console, receives and parses a request from a client process, via an emulator interface, retrieves endpoint service descriptor files according to the request, wherein the endpoint service description files are associated with a web services endpoint for performing a function on behalf of a client program based upon data supplied by the client program, executes a service response script while evaluating said retrieved endpoint service descriptor files to generate a response, and sends the generated response to the client process.