node is fast when the heaviest work is delegated to libuv or native modules (that are performant that is). If you require to do heavy work on v8, it slows dow

node is fast when the heaviest work is delegated to libuv or native modules (that are performant that is). If you require to do heavy work on v8, it slows down significantly. What would I call "heavy work"? e.g: compression, serialization, encryption, image processing... tasks that are bound by CPU and not only I/O. Usually you want to delegate that to a native module and not do that yourself in JavaScript. If you absolutely have to do it in JavaScript, then you need to make sure the task is not blocking the event loop. In order to play nicer with the event loop you inject something like setImmediate or process.nextTick after certain amount of time or iterations... otherwise you will starve other tasks in the loop, notably, I/O. node is also not a really good idea if you need a lot of interprocess communication. It is a very viable alternative, though.