Echo JS 0.11.0

I'm dodging the problem because that's what you probably should do. Deep recursion brings a lot of problems in JavaScript - first of all, the stack's depth.

But you don't seem to even need that stack, since you're ready to use setTimeout, discarding the closure's scope: that's actually a clear sign that you should use another approach, probably iterative. That would give you a good performance boost too.

That's why using setTimeout is generally frowned upon: it's a hack to get over a language limitation that could be solved with other, more efficient techniques.

So I don't recommend using setTimeout, because I don't recommend using recursion in the first place. Tail call optimization, where available, could solve the depth problem but it won't yield a performance as good as an iterative approach.