google logo
Google· ML Engineer (L4/L5)

Google ML Engineer (L4/L5) Interview Experience, Hire?

Posted
29 Apr 2026
682 reads

Summary

I completed four interview rounds for a Google ML Engineer (L4/L5) role, including ML system design, Googliness, and two coding rounds, and ultimately received a hire/strong hire outcome.

How it went

🚀 Google ML Engineer (L4/L5) Interview Experience, Hire? 🤞

Total Rounds: 4 (2 Virtual + 2 Onsite)

I recently went through the Google ML loop and wanted to share a realistic breakdown — including mistakes, recoveries, and where things could go either way.


🔹 Round 1 — ML System Design (Virtual)

Problem: Design a Google Reviews–like system

We covered:

  • NLP pipeline for reviews
  • Deep dive into BERT
  • Trade-offs: LLMs vs smaller models (latency, cost, quality)
  • Unsupervised techniques for clustering / summarization

💡 Strong back-and-forth, deep discussion on modeling choices

Verdict: Hire (H) / Strong Hire (SH)


🔹 Round 2 — Googliness (Virtual)

Behavioral + situational:

  • Ambiguous scenarios
  • “Most complex project”
  • Decision-making under uncertainty

⚠️ What went wrong:

  • Answers weren’t as structured
  • Missed depth in a few responses

📩 Recruiter feedback: Mixed

Verdict: Leaning Hire (LH)


🔹 Round 3 — Onsite Coding (Graphs + Heaps)

Problem:

  • Movies with similarity relationships (transitive)
  • Query:
    • Highest-rated movie
    • Tie → lexicographically smallest
    • Follow-up → Top K movies

Approach:

  1. Build graph
  2. DFS to get connected component
  3. Initially used max heap

💥 Twist: Interviewer questioned heap usage → suggested a variable

👉 Then came follow-up: Top K movies

Recovery:

  • Switched to min heap of size K
  • Remove smallest when size exceeds K

💡 Initial approach scaled well for follow-up

⚠️ Minor hiccups:

  • Forgot to exclude query movie initially
  • Brief stumble on heap internals (recovered)

Verdict: Hire (H) / Strong Hire (SH)


🔹 Round 4 — Onsite Coding (DP / Combinatorics)

Problem:

Count subsets where: sum(subset) > total_sum / 2

Example: [1,3,4], total = 8 → threshold = 4
Valid → [1,4], [3,4], [1,3,4] → answer = 3

Approach:

  • Started with recursion (pick / not pick)
  • ❌ Bug in base case → overcounting
  • Switched to DP

💡 Key idea: Once sum > threshold → all remaining subsets are valid

⚠️ Still had a counting mistake, but discussion was decent

Verdict: Leaning Hire (LH)


📊 Final Self-Evaluation

RoundRating
ML DesignH / SH
GooglinessLH
Coding 1H / SH
Coding 2LH

🧠 Honest Take

Strengths:

  • ML depth
  • Problem solving
  • Ability to adapt mid-interview

Weaknesses:

  • Behavioral structure
  • Edge-case precision under pressure

👉 Feels like a borderline but positive loop overall


🤔 Question

Given:

  • 2 strong signals
  • 2 leaning hire

👉 Does this typically convert to an offer at Google?

Would really appreciate honest feedback — I might be over/underestimating.

Questions asked (2)

  1. 01

    Movies Similarity Graph - Highest Rated Query and Top K

    Data Structures & Algorithms

    Given a set of movies with similarity relationships that are transitive, you are asked to:

    1. Find the highest‑rated movie within the connected component of a query movie. If multiple movies share the highest rating, return the lexicographically smallest title.
    2. Follow‑up: Return the top K movies (by rating, with the same tie‑break rule) from that component.

    The problem requires building a graph of movies, performing a DFS/BFS to identify the component, and then selecting the appropriate movies using heap or other selection techniques.

  2. 02

    Count Subsets with Sum Greater Than Half of Total

    Data Structures & Algorithms

    Given an array of positive integers, count the number of subsets whose sum is strictly greater than half of the total sum of the array.

    Example: Array = [1, 3, 4] Total sum = 8 → threshold = 4 Valid subsets: [1, 4], [3, 4], [1, 3, 4] Answer = 3

Know someone preparing? Send it to them:WhatsAppLinkedInX

Interviewed at Google recently?

Write up your rounds while you still remember the questions. It helps the next person more than you would think.

Share your experience
Discussion 0

Questions for the author, or how your own interview compared.

Join the discussion

Sign in with Google to comment or ask the author a question.

No comments yet

Be the first to share your thoughts and start the discussion!