Vert.x is what you're looking for. That being said, async/Callbacks tend to create a pile of spaghetti, with no measurable performance gain. It's certainly a s

Vert.x is what you're looking for. That being said, async/Callbacks tend to create a pile of spaghetti, with no measurable performance gain. It's certainly a style of doing things and it creates an odd abstraction that really doesn't mirror the way our [current] computers operate. The benefit of "fibers" or "green threads" is they are less of a jump and doesn't involve rewriting everything.