Next.js in Practice · Part 0715 min read
Server Actions and Forms
How 'use server' functions become Server Actions in Next.js 16, from action IDs and encrypted closures in the compiler, through the client dispatch queue and the POST request, to the origin check, body limit and single-roundtrip re-render in action-handler.ts, plus forms with useActionState, useFormStatus, useOptimistic and next/form.