From the webpage:
MorganaXProc is an implementation of W3C’s XProc: An XML Pipeline Language written in Java™. It is free software, released under GNU General Public License version 2.0 (GPLv2).
The current version is 0.95 (public beta). It is very close to the recommendation with all related tests of the XProc Test Suite passed.
News: MorganaXProc 0.95-11 released
You can follow <xml-project/> on Twitter: @xml_project and peruse their documentation.
I haven’t worked my way through A User’s Guide to MorganaXProc but it looks promising.
Enjoy!