Frontend Engineer · Phone Screen · Coding

Apple — Frontend Engineer ✅ Passed

Level: Senior-Level

Round: Phone Screen · Type: Coding · Difficulty: 6/10 · Duration: 60 min · Interviewer: Neutral

Topics: Virtual DOM, React Hooks, Debounce Function, Server Component, Client Component, Error Handling, Merge Intervals

Location: San Francisco Bay Area

Interview date: 2026-02-11

Summary

Phone Screen

Question: I was asked about Virtual DOM, how it helps in React, Hooks I've used, React 18 Concurrent Hooks, writing a Debounce function, Server/Client components, error handling in React, and a merge intervals coding problem.

Details

The interviewer was a few minutes late and did not turn on her camera. I was asked the following questions:

• What is Virtual DOM?
• How does virtual DOM help in React?
• Which Hooks have you used?
• React 18 Concurrent Hooks
• Write a Debounce function
• Server component / client component?
• How do you handle errors in React?

I was also asked to write code for a merge intervals problem.

My Approach:

For the merge intervals problem, I first clarified the input format and constraints. Then I implemented a solution using a sorted list of intervals. For the other questions, I answered based on my understanding and experience with React.

Key Insights:

• Understanding of core React concepts like Virtual DOM is crucial.
• Familiarity with React Hooks and error handling is important.
• Being able to implement common utility functions like debounce is expected.

LeetCode similar: LeetCode 56