Meta ML Engineer Interview Guide

Are you preparing for a Machine Learning Engineer or Data Scientist role at Meta (formerly Facebook)? This page compiles insights from real interview experiences and candidate journeys to help you navigate the ML hiring process at Meta. Whether you're targeting an E4, E5, or E6 level, the interview patterns, expectations, and question types are fairly consistent across roles.

In this guide, you'll learn what to expect in each round, the technical and behavioral themes typically covered, and tips to help you prepare effectively.

What to Expect in Meta ML Interviews

The ML interview process at Meta emphasizes both deep technical understanding and strong collaboration skills. Interview loops usually include a combination of algorithmic coding rounds, machine learning system design, domain-specific ML problem-solving, and behavioral interviews focused on Meta's values.

Typically, the process involves a recruiter screen, followed by a phone interview (or two), and then an onsite or virtual onsite with 4–6 rounds. For ML-specific roles, the coding rounds are accompanied by discussions around production ML workflows, scalability, and model iteration strategies.

Coding questions test your fluency in solving algorithmic problems using data structures and algorithms. These are time-bound challenges that require clean, optimal, and edge-case-proof solutions. Languages like Python, C++, and Java are commonly used.

The ML domain rounds focus on evaluating your understanding of machine learning theory and how you apply it in practice. Expect to be asked about model selection, training strategies, evaluation metrics, feature engineering, and production-level considerations like retraining cadence and data freshness.

System design interviews test your ability to build scalable, maintainable, and efficient ML systems. You'll often be asked to architect real-world ML pipelines like personalized content ranking, ads targeting, or fraud detection, with a focus on trade-offs, model serving, monitoring, and feedback loops.

Behavioral interviews assess how well you align with Meta’s core values like "Be Bold," "Focus on Impact," and "Move Fast." Expect questions around leadership, collaboration, conflict resolution, and ownership.

Types of Questions Asked

Machine Learning Domain Questions

  • How would you evaluate the effectiveness of a recommender system?

  • Describe a project where your ML model didn’t perform well. What did you do?

  • What’s your approach to preventing model drift in dynamic environments?

  • Explain the difference between AUC and LogLoss. When would you use one over the other?

  • How do you debug models that degrade in production?

  • What data labeling strategy would you use for a cold-start problem?

Coding Questions

  • Implement a bounded-size cache that evicts least frequently used items.

  • Solve variations of graph traversal problems involving weights and constraints.

  • Optimize a sliding window algorithm to detect anomalies in a data stream.

  • Write a function to serialize and deserialize a binary tree.

  • Given two arrays, find a pair with the minimum absolute difference.

Behavioral / Meta Values Questions

  • Tell me about a time you moved fast and broke something. What did you learn?

  • Describe a conflict you had on a cross-functional team and how you resolved it.

  • When did you take initiative without being asked? What was the outcome?

  • What is the most impactful ML project you’ve led and why?

  • How do you prioritize experimentation speed vs model accuracy?

  • Give an example of a bold decision you made that paid off.

Machine Learning System Design

  • You may be asked to design systems like personalized news feeds, ML-driven notification engines, or multi-modal recommendation platforms.

  • Design discussions often involve:

    • Data ingestion and preprocessing pipelines

    • Real-time vs batch training workflows

    • Embedding strategies (single-tower, dual-tower, multi-modal)

    • Feature stores and online inference strategies

    • Feedback loop design and A/B experimentation frameworks

  • Interviewers evaluate your ability to:

    • Break down large systems into components

    • Handle model retraining, versioning, and serving

    • Address latency, scalability, and reliability concerns

    • Apply best practices for monitoring and alerting

    • Balance model performance with product impact

  • You may also be asked to code a component like:

    • Real-time deduplication in a stream processing pipeline

    • Custom ranking function for personalized content

    • Embedding lookup and similarity search in large-scale vectors

Explore Real Interview Experiences

We’ve curated authentic candidate stories covering what each round looked like, types of problems solved, and what made them successful. You can read their detailed walkthroughs below:

Each post offers practical insights into preparation, system design approaches, ML model trade-offs, and behavioral strategy. Ideal for those aiming to succeed in Meta’s highly selective ML interview process.