Emil Kowalski is a Polish front-end engineer best known for his work on production-grade animations for the web — including the open-source vaul drawer component, sonner toast library, and cmdk command palette, all of which have spread broadly across the React ecosystem. He has worked at Vercel and Linear and writes / speaks on the craft of UI animation.
His CourseFlix listing carries Animations on the web — a course on the engineering side of motion design: how to use Framer Motion / motion.dev, the CSS primitives that underlie smooth animation, performance considerations, and the design judgment around when motion helps versus hurts the interface.