Introduction

React Native has evolved differently since 2015, the year when Facebook (now known as Meta) made it available to the public. Initially, this was a simple experiment in the application of the declarative UI paradigm of React in the mobile application domain but has gotten to this exponentially wonderful state as a mature framework serving literally thousands of applications in the global iOS and Android environments. Companies such as Microsoft, Shopify, and Coinbase have impressive applications based on React Native, thus showcasing the power of the technology in building applications that do what they do and transform usage patterns into native-like experiences with minimal perception of changes in terms of developer productivity.

As expected, React Native had its share of challenges, like performance bottlenecks, native module integration complexity, and the infamous ‘bridge’ architecture. All these problems necessitated a transition toward a new architecture. This, in turn, has generated the largest architectural overhaul in React Native’s history.

With the arrival of React Native 0.76, the framework became completely extraordinary, with a totally new architecture that redefines performance, scalability, and developer experience.

This article discusses in detail why this release is going to be a game changer, from the technical updates to what they mean to all React Native developers.

Terms and Concepts

Before we start showing the new improvements and what this version has brought, let’s start with engineering terms, it makes it easier for Tech people to follow and understand the concepts first.

1. Metro Bundler

Metro is the JavaScript bundler used by React Native. Think of it as the pipeline that takes your app’s JavaScript code packages it, and serves it to the mobile application. it does the following:

• Transforming modern JavaScript into code that runs on all devices

• Managing dependencies and creating a single bundle

• Enabling fast refresh during development

• Supporting module resolution and asset management

With this release, Metro has been optimized for faster resolution and more efficient handling of assets, making development smoother and build times shorter.

2. Native Modules

Native Modules allow React Native to communicate with the platform’s native code (Java/Kotlin for Android and Objective-C/Swift for iOS). The New Architecture introduces type-safe Native Modules, which streamline interaction between JavaScript and native code. The removal of the “bridge” reduces overhead, improving performance and reliability.

3. The Old vs. New Architecture

Before diving into what’s new, let’s understand how React Native traditionally worked. In the old architecture, JavaScript and native code communicated through a “bridge” — essentially a JSON message queue. While this worked, it had limitations:

• All data had to be serialized/deserialized

• Communication was asynchronous only

• The bridge could become a bottleneck

The new architecture fundamentally changes this with several key innovations

4. Understanding JSI and the New Bridge

JavaScript Interface (JSI) is at the heart of the new architecture. Unlike the old bridge:

• It allows direct communication between JavaScript and native code

• Enables synchronous communication

• Provides direct memory access between JavaScript and native layers

• Eliminates the need for JSON serialization

5. How React Native Works

React Native relies on a reconciliation process, where UI updates in JavaScript translate into native views via a bridge. Previously, this bridge introduced delays due to asynchronous communication. The New Architecture eliminates the bridge, adopting a Turbo Module system that processes calls directly, leading to a much faster and more seamless experience.

6. Fabric: The New Rendering System

Fabric is a significant architectural change in React Native that aims to improve performance, flexibility, and developer experience. It’s designed to replace the older bridge-based rendering system, offering several key advantages

• Enables direct manipulation of native views from JavaScript

• Supports concurrent rendering

• Improves interoperability with native UI components

• Reduces the memory footprint

7. Codegen and Turbo Modules

• Codegen automates the generation of native code for modules and components, reducing manual errors and ensuring type safety.

• Turbo Modules improve the modularity of the code, enabling more efficient usage of native resources and making it easier to integrate custom functionality.

example

import type {TurboModule} from 'react-native/types';
import {TurboModuleRegistry} from 'react-native';

export interface Spec extends TurboModule {
multiply(a: number, b: number): Promise<number>;
}

export default TurboModuleRegistry.get<Spec>('Calculator');

8. Atomic Batching

Atomic batching groups multiple UI updates into a single operation, minimizing the render overhead. In simple terms, instead of handling changes one by one, React Native processes them all together, making the UI more fluid and responsive.

9. Suspense in React

React Suspense allows developers to handle asynchronous operations, like fetching data, with a cleaner and more declarative syntax. The New Architecture integrates Suspense into React Native, enabling seamless data-loading experiences and reducing boilerplate code.

So, What is new in React Native 0.76?

Here’s what makes version 0.76 stand out:

1. The New Architecture is Default

The New Architecture, after years of development, is now enabled by default. This unlocks faster communication between JavaScript and native code, leveraging features like Turbo Modules and Codegen for improved performance.

2. React Native DevTools

A new React Native DevTools interface provides better debugging capabilities, allowing developers to inspect and optimize their apps more effectively.

Browser Developer Tools are useful for inspecting, debugging, and optimizing applications. Some of the most common features of every browser developer tool are:

1. Elements Inspector

2. Console

3. Network Request

4. Performance Profiler (Analyzing app performance)

3. Improved Performance

3.1. Faster resolution times with Metro around x15 faster

3.2. Reduced app sizes on Android by approximately 3.8 MB due to native library merging:

The React Native team has merged some C++ Dynamic Libraries (libraries that load only at runtime, also known as .so files) into one library (libreactnative.so) for Android. Nicola (from Meta) showed us a demo where an Android app with React Native 0.74 ships with 43 dynamic libraries, but in React Native 0.76, the list of dynamic libraries has been reduced to 10. Ultimately, Android apps are now approximately 3.8MB smaller and have ~15ms less startup time.

3.3. Optimized memory management and thread handling.

4. Modern React Features

The integration of Suspense, Transitions, and automatic batching brings React Native closer to modern React web practices, making the development experience more cohesive across platforms.

5. Backward Compatibility

An automatic interoperability layer ensures that apps using libraries from the old architecture remain functional. This means you don’t need to rewrite your entire app immediately — migration can be gradual.

6. Better Library Support

Most of the popular libraries in the React Native ecosystem have already been updated to support the New Architecture, minimizing friction for developers.

7. Breaking Changes

• Minimum supported iOS and Android SDK versions have increased.

• The react-native-community/cli has been removed in favor of built-in alternatives.

• Deprecated APIs have been cleaned up, paving the way for more streamlined development.

Why Should Developers Be Excited?

The New Architecture is more than a performance boost — it’s a paradigm shift that makes React Native apps more scalable, responsive, and future-proof. Developers can now take advantage of:

• Seamless native integration: Faster interactions with native code without the overhead of the bridge.

• Modern UI paradigms: Suspense and Transitions allow for smoother user interfaces.

• Simpler debugging: With DevTools and automatic batching, identifying and resolving issues is easier than ever.

• There is an increase of around 550% in performance by using the new version, there was proven by Kraken, check the article here: https://blog.kraken.com/product/engineering/how-kraken-fixed-performance-issues-via-incremental-adoption-of-the-react-native-new-architecture

• New Expensify app with the new architecture, read more here: https://blog.swmansion.com/sunrising-new-architecture-in-the-new-expensify-app-729d237a02f5

from: https://blog.kraken.com/product/engineering/how-kraken-fixed-performance-issues-via-incremental-adoption-of-the-react-native-new-architecture

Conclusion

React Native 0.76 marks an ending to the years of toil this framework will always have in its history modernization of the architecture above and beyond being an easy-access-to-all unified codebase for cross-platform apps. For developers, this release promises the construction of faster, robust applications, minus the building pains.

Not only is the New Architecture a technical advancement, but it is also futuristic and prepares React Native to meet the challenges of the next generation in mobile application development. Now is the best time to be a React Native developer and get more into it.

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