I find node.js pretty fast. The V8 engine does compile it to native during the run time using a JIT compiler. While it is not quite up to the level of java, it is comparable. The major lacking is no thread support, but it is a boon in many cases as tracking down runtime bugs in multi threaded environments is sometimes very tough. Threads can be simulated using child processes to some extend, but its the only major drawback as far as i have encountered.