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How Senior Engineers Build React Apps: Deep Dive

Asim Zaidi
6 min readJun 12

React, an essential tool in any senior engineer’s arsenal, has gained acclaim for its powerful capabilities in building interactive web applications. To master React, engineers need an in-depth understanding of its foundational principles, best practices, and proficiency in the application of relevant tools for scalable and maintainable application development. Let’s delve deeper into these practices that senior engineers employ when crafting React applications.

Core React Principles Explained and Exemplified

Understanding React’s fundamental principles is crucial in creating scalable and maintainable applications. Here are a couple of these principles with code examples:

One-way Data Flow: Data in React flows unidirectionally from parent to child components. This structure leads to a predictable data flow, making your code easier to manage and debug. For instance, in the code snippet below, the App component passes data to the ChildComponent:

function App() {
const data = "Data from parent component";
return <ChildComponent data={data} />;

function ChildComponent(props) {
return <div>{}</div>;

Virtual DOM: React’s Virtual DOM, an abstraction of the actual browser’s DOM, optimizes UI updates, ensuring a responsive and fast interface without unnecessary re-rendering or updates.

Advanced Code Structuring and Organization Practices

Senior engineers employ certain strategies to structure their React codebases, as illustrated below:

Component-based Architecture: By structuring applications into self-contained, reusable components, each designed to do a specific task, senior engineers maintain a flexible codebase. For example:

// A simple reusable Button component
function Button({ onClick, children }) {
return <button onClick={onClick}>{children}</button>;

Separation of Concerns: Code is divided into distinct layers, each dealing with its specific responsibility. For instance, separation can be across data layer (handling data fetching and manipulation), presentation layer (handling UI rendering), and a container layer (managing…

Asim Zaidi

Building AI Hub @Apple | Prev: SSWE @Atlassian | Co-Founder | Shipping products users love | Helping people break into tech @