Code Quality Issues Okay, face it. Programmers can get lazy, cut corners, or make mistakes. They also can do quick prototypes, and then forget to rewrite them later. Well, while I can't list mistakes in here, I can list prototype-like segments of code that should be aggressively refactored. This does not list optimization issues, that needs to be done after intense profiling. AttrDef Class - doesn't support Unicode characters (fringe); uses regular expressions Lang - code duplication; premature optimization; doesn't consult official lists (fringe) Length - easily mistaken for CSSLength URI - multiple regular expressions; missing validation for query, fragment and path CSS - parser doesn't accept advanced CSS (fringe) Number - constructor interface inconsistent with Integer Config - "load configuration" hooks missing, rich set* accessors missing ConfigSchema - redefinition is a mess Strategy FixNesting - cannot bubble nodes out of structures MakeWellFormed - insufficient automatic closing definitions (check HTML spec for optional end tags, also, closing based on type (block/inline) might be efficient). RemoveForeignElements - should be run in parallel with MakeWellFormed URIScheme - needs to have callable generic checks mailto - doesn't validate emails, doesn't validate querystring news - doesn't validate opaque path nntp - doesn't constrain path EOL