i find wire protocol programming is easier w/ fsm.el, posted to
gnu-emacs-sources a year (or two?) ago, by its author, Magnus Henoch.
attached is a locally-modified copy (see g-e-s archives for original),
with a couple some small example toys using it, in a gzipped tarball.
the toys don't actually use the network so you can try them on an
isolated emacs.

i propose adding this (modified fsm.el) under lisp/emacs-lisp/, as a
sibling of tq.el, assuming legal stuff can be handled sooner or later.

comments?

thi