Also note that “Facebook reduces the storage it needs to store user photos by 50%” is something that contributes, like, nine-figure dollar savings to the bottom

Also note that “Facebook reduces the storage it needs to store user photos by 50%” is something that contributes, like, nine-figure dollar savings to the bottom line. Facebook does all sorts of crazy stuff to improve performance–I don’t think many people who work there understand how the javascript bundler works, for example. It’s a lot more than something like WebPack.