Hmmm, maybe the performance increases I saw were memory related. For some reason I had not thought to look at that! Moving from XML::Twig to XML::LibXML gave me a 36% speedup in a function that was building a complex structure from raw XML data.

I've gotten the module to work with Cygwin (perl and libs). I did need to make use of rebaseall to get my DLLs in order, though; plus there's a tacit dependency on libiconv (tacit == nobody tells you this, but the module fails to build).

On Solaris I encountered two problems. The first was that http://www.sunfreeware.com/ packages a version of libxml2 that is incompatible with the Perl bindings. I solved that (painfully) by making a package of my own. (If anyone wants a copy, give me a holler; but I cannot support it.) The second was a trivial compilation error in one file (was it memory management?) in the bindings plus pesky configuration minutiae. I sent a patch to the maintainers and I don't know if it's been incorporated since.