Rasmus says that he wrote PHP while building a web-based system for Toronto University. The university didn’t care how he built the system, they just wanted their system, so Rasmus built PHP to make his job easier.

Rasmus’s decision to open source PHP was made when he was getting lots of questions about how he was doing his work, and they had the same needs. Rasmus and the University of Toronto were delighted at the speed of development they were now getting — and that he was fixing bugs in his sleep!

To run a successful open-source project, Rasmus says that you need to cater to four types of people:

• those with simple self interest – they have a need that the project solves
• those looking to express themselves through their code
• to interact with others to get their oxytocin fix
• those who want to make the world a better place

The same motivations that motivate people to join an open source project also motivate people to join an interactive website.

You have to think about how the people think about themselves when they involve themselves in your project. You have to give them some ownership and control…which was hard for me…then again I’m a really lazy guy

In order to build a decent modern web application, you really need to think about what the users think of themselves when they interact with your site. Every single action a user performs with your website improves your site.

Later Rasmus delves into performance profiling and optimising a PHP website using Callgrind/valgrind, as well as some stuff about the ubiquity of cross-site scripting vulnerabilities and other topics.

It’s a great podcast, do yourself a favour and have a listen.