Multiplexing web requests for improved performance

A request multiplexing system is described herein that takes multiple asynchronous requests from a client to multiple server endpoints and multiplexes the requests at the client into a single request to a new server endpoint. The new endpoint demultiplexes the requests at the server, calls the pre-existing separate endpoints to get the correct response for each request, combines the responses into a single multiplexed response, and returns the combined response to the client. On the client side, the response data is split up and handed to the appropriate handlers. From the components' points of view and those of the endpoints on the server, the requests occur just as they originally may. However, new logic on both the client and the server has packaged and unpackaged requests and responses appropriately to accomplish without component modification what formerly involved extensive coordination between developers of various components.