unlikely. they probably have a very dirty repo with tons of binaries, images, blah blah blah. It's highly unlikely they actually wrote 8GB of code, and the 46GB .git directory will be littered with binary blob changes, etc. This is really just to "impress" two people: 1) People who love Facebook 2) People who don't know anything about version control and/or how to do proper version control (no binaries in the scm).

In 2012 the Facebook binary was 1.5GB http://arstechnica.com/business/2012/04/exclusive-a-behind-t...

I cited this interesting paper from Facebook engineers(2013) in another comment :

https://news.ycombinator.com/item?id=7648802

In 2011 they had 10 millions LoC, up to 500 commits a day,

but if we asssume the plots keeps going up like this, now in 2014 it can be pretty big.

Their binary was 1.5GB when the paper was written.

1.5GB binary that includes their dependencies (other binaries).