kquery is a pure-JavaScript css selector engine with full implemention of css3 selector. compatible for all major browsers ie6+/chrome/firefox/opera/safari, only 8.0kB minified and gzipped. smart compiler engine will optimize the query logic, keep these which really needs. it's faster than all Sizzle(jquery) version, nwmatcher, peppy without cache, dojo/query. never cache results, query function was cached, works on both XML/HTML.