> broadly there are four repos: www, fbobjc, fbandroid and fbcode This used to be true, but today these are all in fact the same hg repo (www as a possible exc

> broadly there are four repos: www, fbobjc, fbandroid and fbcode This used to be true, but today these are all in fact the same hg repo (www as a possible exception, I'm unsure). The "sparse checkout" machinery disguises it, but for engineers working cross platform (e.g. React Native) it's routine to make commits that span platforms.