Tachyon is the JavaScript JIT compiler I'm working on for my Ph.D. thesis at the Université de Montréal, under the supervision of Professor Marc Feeley. We're hoping this will make the implementation easier and simpler in the end, as writing code in a dynamic language like JavaScript can boost productivity, and there are some advantages to using the same language in the host compiler as the language that's being compiled. I can tell you that when we run the Tachyon code under V8 (~75KLOC of object-oriented goodness), the performance is nowhere near as good as it would be if Tachyon were written in C++.