At the Zeit conference React core member Andrew Clark showed off an upcoming React feature named Suspense. It can automatically pause the render process of a component if it hasn't got all its data. In can be used to avoid things like spinner showing up too quickly.
Async rendering in React gives us a powerful new set of primitives for addressing longstanding problems in UI development. I'll discuss React's vision for how async rendering can improve data fetching, code delivery, prefetching, view transitions, and more.