React 19 is coming and What's new?

As I eagerly await React 19, let's explore the exciting new features it brings to the table with its release.

React Compiler

One of the most common challenges in React development is avoiding unnecessary re-renders. Although we've had tools like useMemo, useCallback, and **memo **for manual state caching to mitigate this issue, React Compiler promises to address it automatically without requiring manual intervention. This should result in noticeable improvements in performance and the prevention of unwanted re-renders.

The great news is that "React Compiler is no longer a research project: the compiler now powers instagram.com in production, and we are working to ship the compiler across additional surfaces at Meta and to prepare the first open-source release - React Dev".

Action

Another exciting addition is the introduction of Actions, providing a more efficient way to interact with the server. Actions allow you to attach a function to DOM elements such as </form>.

<form action={search}>
 <input name="query" />
 <button type="submit">Search</button>
 </form>

When using an action, React manages the lifecycle of data submission for you, offering hooks like **useFormStatus **and useFormState to access the current state and response of the form action.

By default, Actions are submitted within a transition, ensuring that the current page remains interactive while the action is processing. Additionally, Actions support async functions, allowing the use of async/await in transitions. This enables the display of pending UI with the isPending state of a transition when an async request starts, and maintains the pending UI until the update is applied.

Another noteworthy feature is useOptimistic for managing optimistic state updates, but we won't delve into the details of that just yet.

New Features in React Canary

For those eager to try out new stable features before the public release, React Canary will prove invaluable. This allows React developers to gather feedback from the community before the stable release, facilitating further improvements.

React Server Components, Asset Loading, Document Metadata, and Actions are all available in React Canary already.

There's still more to come. In React 19, additional improvements are on the horizon, including long-requested enhancements like support for Web Components. The focus now is on finalizing these changes, preparing for release, updating documentation for new features, and announcing what's included.

It's clear that significant changes and improvements are on the way, and I can't wait to give them a try. Let me know which feature you're most excited about—I'm personally intrigued by the React Compiler and React Server Components.

For more Info follow https://react.dev/blog