Modern websites, apps, APIs, and even video streams, do not live in one place. There is no single point that we can point to and say “This is the application”. In fact, the modern stack is similar to a tree - a hierarchy that expands from the root of the origin to the leaves of user devices and browsers. What can we learn about modern development by thinking about it this way? And beyond that, how can we improve branches of that tree to make our applications better?