81 upvotes and 1 comment? I'll bite: this is stupid but fantastic. I love seeing things like this, where someone learns (and teaches) a lot about a system, and clearly has fun doing it. Sure, I'd never use morfus in production code, but that's entirely besides the point. I came away with a much better understanding of how types work in Go and that's pretty cool :)
Obviously it's someone with upvoting with bots.
@OP: I think you'll enjoy my own hacking of Go's map type here:
Of course, there are all sorts of reasons why this is A Bad Idea, but it's too fun to resist. :)
This shows how important it is, that the whole Go runtime is written in Go - you can see how things are implemented and also use all constructs in your code.