Google L4 interview

Interview Experience
1

Google - Software Engineer (Frontend) - Phone Screen

Description:
Level: L4 (Mid-Level Frontend Engineer)
Education: Bachelor’s in Computer Science
Years of Experience (YOE): 5

Questions Asked:

  1. JavaScript/React Fundamentals:

    • Why does a React component sometimes render twice in development mode?
    • Explain the difference between useEffect and useLayoutEffect.
    • Implement a custom debounce function.

  2. Data Structures/Algorithms:

    • Problem: Implement a function to find the maximum subarray sum (Kadane’s Algorithm).

      • Example 1:
        Input: [-2,1,-3,4,-1,2,1,-5,4]
        Output: 6
        Explanation: [4,-1,2,1] has the largest sum = 6.

  3. System Design (Frontend Focused):

    • Design a dashboard that displays paginated stock market data.
    • How would you handle caching and re-fetching data efficiently?
    • Walk through how you’d structure React components, manage state, and ensure scalability.

  4. Debugging Exercise:

    • Given a half-finished API integration with a React codebase and failing tests, debug the code until all tests pass.
    • Use Chrome DevTools to inspect why API responses are not rendering correctly.