React 19 Actions in practice

React 19's actions turn form submissions into first-class async transitions. Instead of wiring up onSubmit handlers, isPending states and error boundaries by hand, an action gives you all of that in one place.

useActionState binds a mutation to form state, useFormStatus exposes pending state to child components, and useOptimistic lets the UI update before the server confirms. Together they remove most of the plumbing code a typical mutation needed.

The mental shift: mutations are transitions, not events. Once you model them that way, pending UI, rollbacks and retries fall out naturally.