Your app is bigger and slower than it needs to be. Without rewriting app code we can squeeze more performance out of your code by tweaking Webpack and Babel. These tools are immensely powerful but it’s a delicate dance to get them to play nice. This talk is full of tips and tricks to get you there. After three years of tooling around with Webpack and Babel at Netflix, LinkedIn, and Reddit I’ve gotten some battle-won knowledge that I’d like to share with you all. Some non-intuitive tricks that lead to smaller bundles, faster parse times, browser-engine opts and de-opts, and faster perceived load times. While these examples will use Preact to make examples this apply to any application that uses these two phenomenal tools. You’ll be surprised at what you can do just turning a few knobs.