JavaScript, more than any other resource type, is uniquely positioned to be a massive performance bottleneck on the web. And it starts before we ever get into bundle analysis, or hydration or any other of a number of hot topics. It starts with the seemingly innocent script element. Tucked away within the way that element works is a lot of complexity and numerous side effects that can make or break your sites performance.

In this talk, we’ll take a closer look at how to load JavaScript on a …