[21echoes]

that's what we've done with our API: we have a meta-resource /multi that takes in an ordered array of Request objects, each with a URI, (HTTP)Method, and Parameters. The /multi service then splits these Requests out, sends them off to the "real" server in order (GETs, of course, being parallelizable when next to each other in the provided order), and then composes the responses back into one array of Response objects which gets passed back to the client.

It's honestly amazing to work with, as we can be very strict about our separation of concerns on the backend, while letting the frontend combine bits and pieces as makes sense for a given client interface.