The React.js interview process isn’t just about what you know—it’s about how well you can apply it. From component design and state management to accessibility, performance, security and architecture—top companies expect more than just surface-level answers.

This book is your complete, battle-tested guide to excelling in React.js interviews and confidently stepping into your next role.

Written by Kristiyan Velkov—a Front-end lead, mentor, and Docker Captain who has conducted over 350 technical interviews—this guide delivers the real-world insights, strategies, and questions that hiring teams use to evaluate top-tier developers.

What You’ll Learn

• React Security - Learn how to prevent XSS and CSRF attacks, manage sensitive data securely, and implement secure authentication and route protection.
• Web Accessibility (a11y) - Apply WCAG guidelines, use ARIA roles effectively, ensure proper keyboard navigation, and build accessible user interfaces.
• React with TypeScript- Master advanced typing techniques for components, props, events, and hooks. Use utility types like Partial, Pick, Omit, and Record with confidence.
• Routing with React Router & TanStack Router - Build dynamic, nested, and protected routes. Learn layout routes and how to handle URL parameters and search queries effectively.
• Global State Management - Understand when and how to use Context API, Redux Toolkit, Zustand, and MobX. Learn to prevent unnecessary re-renders and scale state across large apps.
• Data Fetching and Caching - Work with fetch(), Axios, SWR, and TanStack Query. Handle paginated data, background refetching, optimistic updates, and error handling the right way.
• GraphQL and API Integration - Learn how GraphQL compares to REST, write queries and mutations, and integrate Apollo Client. Optimize performance and handle security concerns.
• Testing and Test Strategy - Build comprehensive test suites using Jest, React Testing Library, and Cypress. Learn how to mock APIs, simulate user behavior, and cover complex logic.
• Server-Side Rendering and Next.js - Understand CSR, SSR, SSG, and ISR. Use Next.js to build performant applications with proper caching, dynamic routing, and API routes.
• Micro Frontends and Architecture - Explore how to split large applications, share components and state, and maintain performance and security across micro frontends.
• Deployment and CI/CD - Containerize React apps with Docker, configure CI/CD pipelines with GitHub Actions or GitLab, and deploy to Vercel, Netlify, or AWS with zero downtime.

Who This Book Is For ?

• Intermediate Developers – If you already have experience with React.js, this book will deepen your knowledge, reinforce best practices, and prepare you for mid-level interviews.
• Senior Developers & Experts – If you're aiming for senior or leadership roles, this book covers advanced concepts, performance optimizations, architecture patterns, and real-world problem-solving techniques.

What’s Inside Each Question?

• Detailed Answer – In-depth explanations.
• Short Answer – Quick summaries ideal for rapid review.
• Code Examples – TypeScript-based examples reflecting real-world usage.
• Further Resources – Curated links to trusted documentation and advanced reading.

Whether you're hunting for your next opportunity, preparing for a promotion, or planning a strategic career move, this book delivers the knowledge, clarity, and confidence to help you shine in any React.js interview and stand out from the crowd.