Meta — Machine Learning Engineer ✅ Passed
Level: Senior-Level
Round: Full Journey · Type: Multiple Types · Difficulty: 6/10 · Duration: 300 min · Interviewer: Unfriendly
Topics: Coding, Data Structures, Algorithms, Behavioral Questions, AI Coding, System Design, Harmful Content Detection
Location: Menlo Park, CA
Interview date: 2026-01-06
Summary
Round 1: Coding
Question: Implementation of 药物起灵 (LeetCode 20) using a HashMap initially, then alternative approaches like sorted list and two pointers.
Round 2: Coding
Question: Implementation of 易散拔 (LeetCode 138) and discussion on time and space complexity, including O(1) space complexity.
Round 3: Behavioral (BQ)
Question: Standard behavioral questions, including team conflict, past failures, and future career aspirations.
Round 4: AI Coding
Question: Debugging unit tests and implementing a brute force solution, followed by optimization discussions and implementation. Testing was incomplete due to time constraints.
Round 5: System Design (SD)
Question: Designing a system to detect ads containing weapons, using similar principles to harmful content detection.
Details
Preparation Tips & Key Takeaways
What I Learned
- I learned the importance of being able to discuss multiple approaches to a problem, even if one is the most obvious.
- Debugging and optimizing existing code is a valuable skill for AI/ML engineers.
- Familiarizing myself with common system design patterns for content moderation was helpful.
Recommended Preparation
Coding Practice
- Practice implementing common data structures and algorithms, such as hash maps and sorted lists.
- Focus on problems that require optimizing for space complexity.
System Design
- Study system design patterns for harmful content detection.
- Review common components of recommendation systems, as they share similar challenges.
Behavioral Questions
- Prepare STAR stories for conflict resolution, handling failure, and career goals.
- Practice explaining my problem-solving process and technical decisions.
Resources I Recommend
- HelloInterview for system design preparation.
- LeetCode for coding practice.
Common Pitfalls to Avoid
- Neglecting space complexity optimization.
- Rushing through the debugging process without fully understanding the code.
- Failing to adequately prepare for behavioral questions.
LeetCode similar: LeetCode 20, LeetCode 138