The good old PHP has its reputation of a strong programming framework, which is comparatively cheaper, faster and reliable. But like they say, age is just a number and PHP has enriched its inventory with handful of framework choices to choose from. In a nutshell, PHP is free, open source and flexible - making it a web developer’s go-to for custom web backend development.
In case that seems unconvincing, big-guns like Facebook, Wikipedia, AliExpress and Weibo use PHP as their backend programming language. If it works for such huge stacks, it should work smoothly for anyone - you got no reason to think the other way around.