It's pretty good at most languages I find. the smaller you can make the task, the better results you'll get. I find myself mostly saying, "no, don't add that dependency" or "this code is redundant" when it's wrong. It's barely ever a syntactic failure. Generally speaking though, I find the more adoption the language has, the better the ai is with that language. So it's probably a lot better with javascript and python than it is with golang. But with good direction, it's just fine with go. But you can do lower level things with go, so you have to actually understand data structures and algorithms before you implement something that just doesn't work well for the intended purpose.