Change is the only constant in software, and few languages change like Javascript. One of the biggest changes we’ve seen is that JavaScript is now extremely fast. One of the fastest JavaScript engines in existence is Google’s V8, which powers both Chrome and Node.js. In simple benchmarks, well-optimized JS (JavaScript) executed by V8 often performs at 80-90% of the speed of the corresponding C++ code. This speed is thanks to the immense amount of work that has gone into V8’s JIT (just-in-time) compiler.