OpenAI

OpenAI

Leading AI research laboratory developing state-of-the-art foundation models like GPT-4.

5 Rounds ~21 Days Very Hard
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The Interview Loop

Recruiter Screen (30 min)

Standard fit check, behavioral questions, and resume overview.

Technical Loop (3-4 Rounds)

Deep dive into domain knowledge, coding, and system design.

Interview Question Bank

Data Scientist Coding hard

Given a stream of incoming API requests represented as tuples of (timestamp, user_id, token_count), write a Python algorithm to identify users who are consistently hitting the 99th percentile of token usage within any rolling 5-minute window.

#Streaming Data #Sliding Window #Heaps/Queues
Data Scientist Coding medium

Given a list of user sessions containing timestamps and generated token counts, write an algorithm in Python to classify sessions as 'bot/scraper' vs. 'human' based on generation cadence and prompt frequency.

#Anomaly Detection #Time Series #Python
Data Scientist Coding medium

Write a Python function to parse a massive JSONL file of ChatGPT conversation logs (too large to fit in memory) and compute the rolling 7-day average of messages per session.

#Data Generators #Memory Management #Time Series
Data Scientist Coding hard

Implement a stratified sampling algorithm in Python to select prompt-response pairs for human evaluation (RLHF), ensuring proportional representation across 50 languages and 20 topic categories.

#Sampling #Probability #Data Structures

Difficulty Radar

Based on recent AI-sourced data.

Meet Your Interviewers

The "Standard" Interviewer

Senior Engineer

Focuses on core competencies, system constraints, and clear communication.

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Unwritten Rules

Think Out Loud

Always explain your thought process before writing code or drawing architecture.

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