PostgreSQL is a popular open-source database. But can it handle large-scale applications? In particular, can it scale up to handle large Web applications, with millions of users and many billions of dollars at stake? The answer is “yes,” but that just raises the question of “how,” and what techniques can (and should) be used to scale it up in this way. In this talk, Sean Chittenden describes the aspects of scaling, and some of the different ways and layers that can fail. He then describes how Groupon has tried to reduce the risk of failure, and how they have used PostgreSQL in this context, and the ways that you can tune context appropriately (and inappropriately) to scale it up.