The software world is known to be fast-paced in the sense that, there are always rollouts of new technologies now and then. A key trait of a good developer is the ability to learn as many programming technologies as possible within a short period for specific projects/roles and keep up with updates and trends in the industry. Frontend development is littered with the most amount of frameworks, libraries, and updates to deal with. React is the most popular library for front-end developers due to its usefulness in building robust user interfaces. Improvements have been made by the React team and we are anticipating React 19!
React 19 is upon us and as the React community would agree, we are due for an updated version. The last version released by React was on June 14, 2022, with version number 18.2.0, which is rare for such a big and popular technology. With React 19, we are expecting a slew of significant updates and changes to previous ways of coding with previous versions of the library. As with any update, enhanced performance is the goal. The capabilities of this soon-to-be-released version can be tested, as at the publishing of this article on the Canary version. The stable version is set to be released soon and will house the new features and updates currently running on the Canary version.
New Features and Changes Expected
There are new features that will be taking the place of features you are accustomed to. Some other features are just enhanced and geared to make development with React better.
Automatic Memoization
With React’s current version, we make use of useMemo() and useCallback() as performance optimization techniques to speed up the rendering process of our components – whereby, results of complex function calls are stored and reused when there are no input changes. This comes in handy when dealing with components that re-render frequently. In React 19, memoization will become automatic and doesn’t have to be manually set in code by you. Pretty cool, right?
Use() Hook
This hook will read and asynchronously load a resource such as a promise or a context. It can also be used in loops and conditionals, unlike other React hooks.
Use() hook can be used to fetch data, therefore, replacing useEffect().
Use Client and use Server Directives
React 19 is coming with support for both the use of Client and use Server directives. This is an important aspect as they allow developers to write both client-side and server-side code in the same file. Components will be rendered on the server which makes for better SEO, faster page load times and easy data fetching.
Action
Working with forms will become a lot easier in this anticipated version as we don’t need to submit a form handler and make our request from a function for example. React 19 will enable us to use an action attribute on forms to handle the submission! Form actions will also work synchronously and asynchronously, making working with forms a lot easier.
New form handling hooks will be:
• useFormStatus() – to access the current status of form operations.
• useFormState() – for response of form operations.
useOptimistic() Hook
This hook is already in its experimental phase but, is set to be made stable in React 19. This hook will be used to provide temporary updates to the User Interface while waiting for the server to respond for instance. This will make for a faster and more responsive experience.
Document Metadata
The days of using third-party packages for SEO and metadata is coming to an end. The incoming version will have in-built support like titles, descriptions and keywords.
Tags can now be placed anywhere within a component’s JSX and it will work for both client and server components.
No more forwardRef
This feature allows for the passing of a ref through a component to its child and is useful when access is needed to a child DOM element or React component instance from a parent component. forwardRef will no longer be used but instead, ref will be passed as a regular prop.
Asset Loading
Being greeted with unstyled content during page load seems to be a common theme when visiting some websites which isn’t ideal. React 19 will be integrating asset loading with Suspense to ensure assets are ready before display.
Web components support
Better component support will be made available in this newer version, making building reusable components much easier.
No more React.Lazy
The technique of deferring loading of non-critical resources until they are needed will now be done by default to reduce the initial load time of a webpage which means there will be no need for React.Lazy.
<Context> replacing <Context.Provider>
Use(promise) will replace throw promise which improves the handling of asynchronous data loading.
I’m excited to see how it improves both the developers’ experience when working with React web applications and the user's experience when interacting with the application. There is a Canary version that is experimental, in case you want to try out the features and see firsthand how the new features work. You can connect with me on LinkedIn as I frequently write on front-end development and other programming topics.