> The binary executable is just one part of the Facebook application stack, of course. Many external resources are referenced from Facebook pages, including JavaScript, CSS, and graphical assets. Those files are hosted on geographically distributed content delivery networks (CDNs).
It doesn't say whether or not these are part of the binary, but I'd suspect they aren't used as the CDN origin. You'd want these (randomly-but-uniquely named) resources to be pushed out to the CDN and warmed up before a deploy to avoid a thundering herd[1] problem from millions of users.