The frontend landscape changes at a relentless pace. New ideas seem to appear every month. How can you possibly keep up? I'm on the Firefox Developer Tools team, and we are starting to move towards React and Redux for our frontend. I will explain these choices, the reasons behind them, and how we're migrating old code. Our minds can only keep up with a certain level of abstraction, and it's important to choose abstractions that solve fundamental problems rather than shallow ones. The right abstractions will make an order of magnitude difference in power and simplicity, and the wrong ones can be deadly. It's important to estimate the cost of every abstraction, and be ruthless about keeping it as simple as possible.