Picture a scenario where you write an app just once, and it seamlessly runs across various platforms. That’s the ambitious goal of React Strict DOM (RSD, react-strict-dom). In the React ecosystem, we grapple with React DOM for web applications and React Native for native platforms (including React Native for iOS, Android, MacOS, Windows, TVOs, VisionOs, and Skia). This division often translates to extra effort and occasional headaches. Enter RSD—a tool designed to simplify the process, allowing us to build apps without fretting about the specific platform.

What is React Strict DOM?

React Strict DOM is a mechanism that warns about potential issues in a React application. It can detect problems that a linter might not catch, such as deprecated methods in class components. Strict DOM mode is part of the React package and does not require any external dependencies. With strict mode, developers can identify and fix errors before they reach production, significantly improving code quality.

Core Principles of the Library

The React library is an open-source JavaScript library for building web applications. React is written in JavaScript but can also be used with TypeScript. The React library is based on the concept of the Virtual DOM, which enables efficient rendering and updating of applications. React is used to build frontend applications, such as websites, mobile apps, and desktop applications. Thanks to its core principles, developers can create dynamic and responsive user interfaces that run smoothly across various devices.

What’s New in React 18

React 18 introduces numerous new features and improvements designed to enhance the performance and usability of applications. One of the primary goals of React 18 is to improve the efficiency of rendered applications. This version includes features such as automatic batching and the Suspense component. With these enhancements, building applications becomes more efficient, and users can enjoy smoother and more responsive interfaces.

Concurrent Rendering Mode

Concurrent Rendering Mode is a new feature in React 18 that enables state updates to be grouped to improve performance. This functionality is available only in React 18 and newer versions. Concurrent Rendering Mode allows for prioritizing, queuing, and interrupting renders within an application. As a result, applications can better manage resources and provide smoother user experiences, even during complex operations. Suspense The Suspense component is a new feature in React 18 that allows displaying a fallback component while the main component is still loading. Suspense is available only in React 18 and newer versions. With this feature, developers can better manage data and component loading, resulting in smoother and more responsive applications. The Suspense component improves user experience by showing a placeholder during content loading.

What exactly is React Strict DOM in Strict Mode?

React Strict DOM (RSD) takes a distinct approach compared to React Native for Web. Rather than relying on a separate implementation, RSD leverages Web APIs directly to render components, enabling direct interaction with the DOM tree. To achieve this, it introduces two lightweight polyfills that act as intermediaries, translating its APIs into both React Native and React DOM primitives. RSD prioritizes the use of functional components, which are key to React’s modern architecture, contrasting them with older class components. Additionally, React Strict DOM closely integrates with StyleX, a CSS-in-JS library developed by Meta. This integration provides a unified styling solution across platforms, allowing developers to style their applications with familiar CSS-like syntax while benefiting from the performance and safety features of StyleX. Within the React ecosystem, react-strict-dom represents a significant advancement. It is emerging as the natural successor to React Native Web, offering the ability to build universal applications from a single codebase. These applications can seamlessly target multiple platforms, leveraging each platform’s APIs without trade-offs or performance issues, particularly in developer mode. In this mode, various checks and warnings help identify potential issues before production deployment. In short, React Strict DOM bridges the gap between platforms, promoting code efficiency, consistent styling, and enhanced performance for modern React applications.