Yes, that’s what I said in the above comment. They have a git frontend as well. I’m sure someone at Google has made one-off front ends for other random stuff as well. Point is, the monorepo isn’t Mercurial nor git, whereas for Dropbox it is git (and likely Mercurial doesn’t scale for that use case), which was the point (“shame it’s not mercurial”) in the original comment I was responding to.