Use sockets for communication?

[atomontage]

Seems a lot cleaner, no more subprocess output mixing problems, easy bidirectional communication for callbacks and you could also provide an optional asynchronous api, with no extra work.

[skeeto]

That's a really good idea. I've run into similar subprocess issues on other Elisp projects and this approach would also help with those as well. The process' standard IO would just be for initially communicating a port.