Required files
libxml_ruby
libxml/error
libxml/parser
libxml/document
libxml/namespaces
libxml/namespace
libxml/node
libxml/attributes
libxml/attr
libxml/attr_decl
libxml/tree
libxml/html_parser
libxml/sax_parser
libxml/sax_callbacks
libxml/schema
libxml/schema/type
libxml/schema/element
libxml/schema/attribute