Machine Learning Engineer · Phone Screen · Coding

[ OK ] 9e939a57-06a7-4d13-9782-0de10252c0fc — full writeup

[ INFO ] category: Behavioral · Coding difficulty: 3 freq: first seen: 2026-02-28

[3][CODING]Machine LearningData StructuresAlgorithms

$ cat problem.md

Pinterest — Machine Learning Engineer ❌ Failed

Level: Senior-Level

Round: Phone Screen · Type: Coding · Difficulty: 3/10 · Duration: 60 min · Interviewer: Unfriendly

Topics: Machine Learning, Data Structures, Algorithms

Location: San Francisco Bay Area

Interview date: 2025-08-15

Got offer: False

Summary

I had a phone screen with an engineer. After a brief discussion of my experience and some basic machine learning questions, I was asked to implement an IP address blocking system.

Details

The coding question was not a standard LeetCode problem. I was asked to implement a system to determine if an IP address is on a blocked list, discuss the complexity, and improve the solution. I felt I answered well, addressing implementation, optimization, and code cleanliness. However, I received a rejection the next day.

My approach was:

Implement the core logic
Optimize for different scenarios
Ensure clean and readable code

user@intervues:~/experiences/pinterest$