I recently went through the interview loop for Staff and senior level roles at FAANG plus non fang companies and received several top of the band offers. I now conduct 1-3 interviews weekly and I also run frontendlead (dot) com, a structured approach for frontend engs preparing for interviews.

Here are some tips for you:

React Questions

* What are React hooks, and when should you use useMemo vs. useCallback?
* How does the React rendering lifecycle work? What triggers a re-render?
* Explain the difference between controlled and uncontrolled components.
* What is reconciliation in React? How does React Fiber improve performance?
* What are higher-order components (HOCs), and when should you use them?
* How do you manage global state without Redux?

JavaScript Questions

* Explain closures and provide a real-world example.
* What is prototypal inheritance, and how does JavaScript handle it?
* How does `this` behave in different JavaScript contexts?
* What’s the difference between `var`, `let`, and `const`?
* How does event delegation work, and why is it useful?
* Explain the event loop and how JavaScript handles asynchronous operations.

Build an App (Live Coding)

* Build a to-do list with add/edit/delete functionality.
* Create a search bar with real-time filtering using `useState`.
* Implement a dark mode toggle using React Context.
* Fetch and display data from an API using `useEffect` and handle errors.
* Make tiktactoe game
* Make a stop watch or star rating system

The big call out here is to not only complete all requirements on time but also setup yourself for success with maintainable production level code, which can easily be tested. Bonus tips if you can also write some basic tests. Consider design patterns as well such as MVVM for react, I have an article for that on frontendlead.

Frontend System Design

*How would you structure a large-scale React application?
* What are the trade-offs between Redux, Context API, and Zustand?
* How would you optimize the initial page load time for a React app?
* Explain lazy loading and dynamic imports in React.
* build the frontend for Facebook
* think about accessibility/localization
* how would this scale? How do you identify and improve bottle necks?
* how do you measure success?
* how do you test things?
* remember to discuss the trade offs for literally everything you bring up


Pro Tip:
Before coding, clarify constraints and talk through trade-offs. Many system design examples with videos are also available on the platform.

Behavioral questions / hiring manger round
* this is the make it or break it round , honestly, keeping it real, every behavioral question I’ve been asked is on frontendlead and more. Practice and maybe jot your answers down before the interviews but don’t sound rehearsed, play it cool and be authentic, don’t bullshit your way, people will easily see that.

Bonus Tips

1. Consider free and paid alternatives with a more structured approach to prepping for frontend interviews. Full disclosure, I am the creator of FrontendLead.com, which offers a structured approach to preparing for front-end specific interviews at top tech companies, with company particular questions. (30-day money-back guarantee)
2. Use other platforms (free and paid) to also help you prepare.

Like solving a technical problem, you should always have multiple tools in your tool belt to solve a problem.