Twitter / X

Real-time social platform with petabyte-scale data and ML ranking systems.

4 Rounds ~14 Days 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

All Roles Backend Engineer 9 Cloud Engineer 3 Data Engineer 9 Data Scientist 5 DevOps Engineer 3 Full Stack Engineer 6 Machine Learning Engineer 8 Software Engineer 15

All Topics Algorithms 9 SQL 7 System Design 7 Culture Fit 5 Big Data Frameworks 5 Data Modeling 1 Data Validation 1

Data Engineer • Coding • medium

Parse a log file of Twitter events to find the top 10 most active users in a given 1-hour window.

#Log Parsing #Hash Maps #Sorting #Priority Queue

Practice

Data Engineer • Coding • medium

Implement a sliding window algorithm to count the number of tweets containing a specific hashtag in the last 5 minutes.

#Sliding Window #Queues #Real-time Processing

Practice

Data Engineer • Coding • hard

Given K sorted streams of tweet IDs (in chronological order), merge them into a single sorted stream.

#Heaps #Pointers #Stream Processing

Practice

Data Engineer • Coding • hard

Find the shortest path between two users in the Twitter follower graph.

#Graphs #BFS #Bidirectional Search

Practice

Data Engineer • Coding • medium

Implement a rate limiter for the Twitter API using a token bucket algorithm.

#Concurrency #System Design #Object-Oriented Design

Practice

Data Engineer • Coding • easy

Given a list of trending search terms, group the anagrams together.

#Strings #Hash Maps

Practice

Data Engineer • Coding • medium

Design an algorithm to find the Top K frequent words in a continuous stream of tweets (Heavy Hitters problem).

#Count-Min Sketch #Heaps #Streaming Algorithms

Practice

Data Engineer • Coding • medium

Implement an LRU Cache to store recently accessed user profiles.

#Linked Lists #Hash Maps #Caching

Practice

Data Engineer • Coding • medium

Implement a Trie data structure to support Twitter search autocomplete.

#Trees #Trie #String Manipulation

Practice

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The "Standard" Interviewer

Senior Engineer

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

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Think Out Loud

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

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