NOTE: Zorba is now hosted on Launchpad. Please visit our project homepage (http://www.zorba-xquery.com/) or our Launchpad page (https://launchpad.net/zorba) for the latest news and information!
Zorba is a general purpose XQuery processor implementing in C++ the W3C family of specifications. It is not an XML database. The query processor has been designed to be embeddable in a variety of environments.
to many problems to use it with ruby unter windows system
One of the most complete and stable XQuery engine.