> use a performant web server i.e. not PHP or Ruby. PHP in an ordinary deployment behind Apache2 or nginx is very fast. If you're writing a Web service and you

> use a performant web server i.e. not PHP or Ruby. PHP in an ordinary deployment behind Apache2 or nginx is very fast. If you're writing a Web service and your top two criteria for the language are "fast" and "scripting language" and PHP doesn't at least make your short-list, you've likely screwed up. It's the one to beat—you pretty much have to go with something compiled to have a good chance of beating it at serving dynamic responses to ordinary Web requests, and even then it's easy to screw up in minor ways and end up slower. Persistent connections, sure, maybe you want something else, but basic request-response stuff? Performance is not a reason to avoid it, unless your other candidate languages are C++ or very well-tuned and carefully written Java or Go, something along those lines. Speed-wise, it is certainly in a whole other category from Ruby or Python (in fact, even "speedy" Nodejs struggles to match it). Now, WordPress is slow because a top design goal is that it's infinitely at-runtime extensible. And lots of PHP sites are slow for the same reason that lots of Ruby, or Node, or Python, or Java, or .Net, or whatever, sites are slow: the developer was very bad at querying databases.