How Much Performance Difference Can There Be Between Different Languages?

A lot of companies start with something that's quick and easy and then transform it, right? You look at Facebook, they were so dependent on PHP that they literally made a VM to runPH called hack. It isn't until you get a large enough team that you can change everything in this code base if we say, hey, what do we gain by doing this little bit differently? A lot of times prioritizing just more features and more things is simply better for money. And I think I remember saying that quite a long time ago.