0PricingLogin
Next.js 15 Fullstack (App Router + Server Actions) · Lesson

Optimistic UI Updates

Implement optimistic UI patterns with Server Actions to provide instant feedback to users before server confirmation.

Instant Feedback with Optimistic UI

Imagine clicking 'Like' on a post. Does it update instantly, or do you wait for a spinner?

Optimistic UI is a technique where the user interface updates immediately after an action, *before* the server confirms it. This gives users instant feedback and makes your app feel much faster and more responsive.

How Optimistic UI Works

The process is simple:

  • User Action: The user performs an action (e.g., submitting a form).
  • Instant UI Update: Your UI immediately updates to reflect the *expected* outcome.
  • Server Action: In the background, a server request (like a Next.js Server Action) is sent to perform the actual operation.
  • Reconciliation: If the server action succeeds, the UI stays as is. If it fails, the UI reverts to its previous state.

This creates a smooth, uninterrupted user experience.

All lessons in this course

  1. Optimistic UI Updates
  2. File Uploads with Actions
  3. Validation & Error Handling in Server Actions
← Back to Next.js 15 Fullstack (App Router + Server Actions)