Meta — Software Engineer ✅ Passed
Level: Senior-Level
Round: Virtual Onsite · Type: Multiple Types · Difficulty: 7/10 · Duration: 360 min · Interviewer: Unfriendly
Topics: String manipulation, Tree construction, Debugging, System Design, Behavioral Questions
Location: Menlo Park, CA
Interview date: 2026-01-18
Summary
Round 1: Technical Phone Screen
Question: Project discussion and efficient implementation of the pow function.
Round 2: Coding
Question: String cancellation with same characters and building a tree from a string representation.
Round 3: AI Assisted Coding
Question: Maze debugging with AI assistance, including identifying and fixing bugs related to pathfinding and door traversal.
Round 4: System Design
Question: System design for an ad clicker with scaling to 100M requests/second, advertiser dashboard, and storage.
Round 5: System Design
Question: Status feature for WhatsApp and how to search the statuses efficiently.
Round 6: Behavioral (BQ)
Question: Project involving cross-team collaboration, a failed project, and reflections on the experience.
Details
Preparation Tips & Key Takeaways
What I Learned
- Debugging with AI can be helpful but understanding the underlying logic is crucial. I need to be able to identify the bugs myself, before relying on AI.
- System design interviews require a deep understanding of scaling, storage, and user experience. I should focus on common system design patterns.
Recommended Preparation
Coding Practice
- Focus on string manipulation problems and tree-based data structures.
- Practice debugging code in a maze-solving context.
System Design
- Study high-throughput systems, caching strategies, and database design.
- Review common system design patterns for ad tech and social media features.
Behavioral Questions
- Prepare STAR stories for cross-team collaboration and failure scenarios.
- Practice articulating my thought process and lessons learned from past projects.
Resources I Recommend
- LeetCode for coding practice.
- System Design Primer for system design concepts.
- Mock interviews to practice behavioral questions.
Common Pitfalls to Avoid
- Over-reliance on AI assistance without understanding the underlying logic.
- Neglecting the importance of scalability and storage in system design.
- Failing to adequately prepare for behavioral questions with specific examples.