Imagine you have two choices of how to build something: top-down and controlled, with a few people playing a master designer role, or bottom-up and free-for-all, with nobody playing an explicit architect role. Which one do you think would make the better product? “The Cathedral and the Bazaar” is an essay exploring this question for open source software, and making an argument for the bottom-up approach. It’s not entirely intuitive that projects like Linux or scikit-learn, with many contributors and an open-door policy for modifying the code, would be able to resist the chaos of many cooks in the kitchen. So what makes it work in some cases? And sometimes not work in others? That’s the topic of discussion this week.