You can ask V8 to dump the assembly or intermediate representation or you can just run it with --trace-deopt and it'll tell you most of the time (generally) wha

You can ask V8 to dump the assembly or intermediate representation or you can just run it with --trace-deopt and it'll tell you most of the time (generally) what's slowing your code down. > I'm asking too much from a language without value types JavaScript has value types, what it doesn't have is user defined value types. BigInts are coming (stage 3 already!) though.