The Frontend Interview Roadmap 2026: From Junior to Senior
A comprehensive guide on what to master for frontend interviews in 2026, including React 19, Next.js 15, AI-assisted coding, and advanced system design.
The frontend landscape has shifted dramatically over the last two years. While the fundamentals of JavaScript and DOM manipulation remain core, the expectations for 2026 have evolved to include deep knowledge of server-side integration, AI workflows, and sophisticated performance patterns.
1. The React 19 Revolution
React 19 has simplified many things while introducing new complexities.
- Actions & Forms: Mastering the new
useActionStateanduseFormStatushooks is mandatory. - Compiler Knowledge: While the React Compiler handles much of the optimization, you still need to understand why and where it might fail.
2. Next.js 15 Mastery
Next.js continues to dominate the production landscape.
- Server Actions: Real-world proficiency in building secure, type-safe data mutations.
- Streaming & Suspense: Going beyond basic implementation to handle complex loading states and SEO.
3. The Rise of AI-Assisted Coding
Interviews in 2026 are increasingly allowing AI tools (like Copilot or Cursor). The focus is no longer on syntax, but on Architectural Oversight. Can you direct the AI to build something scalable? Can you spot the security loophole in its output?
4. Advanced System Design
Frontend System Design now includes:
- Offline First & Sync: Handling data synchronization in complex PWAs.
- Edge Deployment Logic: Understanding what should run at the edge vs. the server vs. the client.
Stay ahead by focusing on the "Why" and the "Architecture" rather than just the "How."