Our "Paintastic 2000" software is selling like hotcakes, but now the bosses are asking for more features than ever. Our code is bloating—fast! We need new strategies to keep our code slim, decoupled, and legible as the app outgrows its original abstractions. This time, Chris Powers calls upon the value of the "I" in SOLID: the Interface Segregation Principle. At first blush this principle might not seem to offer much value in JavaScript. After all, how can a language without interfaces possibly benefit from the Interface Segregation Principle?! Thankfully Chris is able to demonstrate to us how this principle genuinely applies to JavaScript, both in metaphor and in live coding. Along the way, Chris explores the misleadings of multitasking, the focus of flow state, and the gravity of Gantt charts. Software development teams can make huge gains not just by changing the quality of their code, but also by improving the quality of their time. Chris discusses the intrinsic motivators that p