Machine Learning Engineer · Onsite · Multiple Types

OpenAI — Machine Learning Engineer ✅ Passed

Level: Senior-Level

Round: Onsite · Type: Multiple Types · Difficulty: 7/10 · Duration: 180 min · Interviewer: Neutral

Topics: Machine Learning, Algorithms, Python, Numerical Computation, Arrays

Location: San Francisco Bay Area

Interview date: 2026-01-15

Summary

I had three technical rounds: two coding rounds and one ML round. After initially passing, I was asked to complete an additional ML coding round.

Details

I interviewed in January for a Machine Learning Engineer role. The onsite interview consisted of three technical rounds:

• Two coding rounds (disease spread, Python version).
• One ML round (classifier with different annotators).

I initially received a positive notification, but then I was informed that I needed to complete an additional ML coding round. The prompt for the additional round was:

"In this 60 min interview, you’ll implement a simple numerical routine involving arrays and basic math operations. The task focuses on accuracy, performance, and thoughtful handling of edge cases. No domain-specific knowledge is required, though experience with Python and vectorized computation (e.g., NumPy) will be helpful."