Oh, that's really cool, I didn't know they had this project in the pipe. I agree that bundling tools with the compiler is such a great idea; a build tool built specifically for the language can assume so much more and do so much more, it's a net win.
https://github.com/mozilla/rust/pull/4610
Independence from external build tools is one of the coolest features of Go, so I'm really excited about seeing more languages take this route.