It’s hard to imagine a form that could be simpler: two fields, two buttons, and one link. Yet, it turns out this form was preventing customers from purchasing products from a major e-commerce site, to the tune of $300,000,000 a year. What was even worse: the designers of the site had no clue there was even a problem.

By building on the open source software and community, we were able to create a top-tier web site with a minimum of cost and effort. The system we ended up with is scalable to huge amounts of traffic. It runs on mostly commodity hardware making it easy to grow when the need arises.