Guix

XML::Twig is an XML transformation module. Its strong points: can be used to process huge documents while still being in tree mode; not bound by DOM or SAX, so it is very perlish and offers a very comprehensive set of methods; simple to use; DWIMs as much as possible.

What it doesn't offer: full SAX support (it can export SAX, but only reads XML), full XPath support (unless you use XML::Twig::XPath), nor DOM support.