Although Chrome's performance beats the current stable version of Firefox, Arstechnica's benchmarks show that Mozilla's next-generation JavaScript engine actually outperforms V8.  Mozilla is using tracing optimization techniques and Adobe's open source nanojit to increase the execution speed of SpiderMonkey, the JavaScript runtime engine in the Firefox web browser. The new engine, which is called TraceMonkey, delivers unprecedented JavaScript performance. The new optimizations have already landed in the latest Firefox nightly builds (but still have to be manually enabled) and will likely be included in Firefox 3.1. JavaScript creator and Mozilla CTO Brendan Eich ran the SunSpider JavaScript benchmarks against Chrome and the latest TraceMonkey-enabled Firefox build, which includes some recent improvements. The benchmarks show that TraceMonkey is clearly faster than Google's V8. Mozilla believes that the optimization technique used in TraceMonkey has the potential to unlock even more performance improvements.