James Wright is the author. See the project page for details.
It is installable using Quicklisp:
The darcs repository is publicly available for those who want to be able to track the up-to-the-minute, possibly-broken bleeding-edge. To get a copy of the current darcs repo:
darcs get http://chumsley.org/jwacs/unstable
ASDF-install package (obsolete) http://chumsley.org/jwacs/downloads/jwacs-current.tar.gz