Making use of C++ to speed up PHP

Question

I saw this post on Sitepoint quoting a statement by Rasmus Lerdorf which goes (according to Sitepoint) as follows:

How can you make PHP fast? Well, yo

Answer 1

There's an introduction to writing php extensions at http://devzone.zend.com/article/1021 (published in 2005, might be a bit outdated).
You can also use tools like swig to build wrappers for existing C/C++ code.