Twitter / X
Real-time social platform with petabyte-scale data and ML ranking systems.
4 Rounds
~14 Days
Hard
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
Software Engineer
•
System Design
•
hard
Design the X 'For You' timeline, focusing on how to handle the fan-out problem for users with millions of followers.
#Scalability
#Caching
#Graph Processing
#Stream Processing
Software Engineer
•
System Design
•
medium
Design a distributed rate limiter for the X API to prevent abuse while allowing burst traffic for premium (X Premium) users.
#Distributed Systems
#API Design
#Concurrency
Software Engineer
•
System Design
•
hard
Design the Trending Topics system. How do you process millions of tweets per minute to find top hashtags in real-time?
#Stream Processing
#Heavy Hitters
#Data Pipelines
Software Engineer
•
System Design
•
medium
Design Snowflake: A distributed unique ID generator for tweets that is highly available and sortable by time.
#Distributed Systems
#Bit Manipulation
#High Availability
Software Engineer
•
System Design
•
hard
Design a View Count system for tweets that updates in near real-time and handles viral spikes without overwhelming the database.
#Event Aggregation
#Caching
#Database Sharding
Software Engineer
•
System Design
•
hard
Design a push notification system that alerts millions of users within seconds when a highly followed account posts a new tweet.
#Pub/Sub
#WebSockets
#Mobile Push
Software Engineer
•
System Design
•
hard
Design X Search. How would you index tweets to allow full-text search within seconds of posting?
#Search Engines
#Inverted Index
#Real-time Indexing
Software Engineer
•
System Design
•
medium
Design the Community Notes feature, including the data model for contributors, ratings, and the algorithm pipeline to display the most helpful note.
#Data Modeling
#Graph Algorithms
#Event Driven
Software Engineer
•
System Design
•
hard
Design an Ad Click Aggregation system that processes billions of events per day and provides real-time analytics to advertisers.
#Big Data
#OLAP
#Exactly-once Semantics
Software Engineer
•
System Design
•
hard
Design a system to detect and mitigate bot swarms liking a specific tweet in real-time.
#Machine Learning Infrastructure
#Anomaly Detection
#Stream Processing
Difficulty Radar
Based on recent AI-sourced data.
Meet Your Interviewers
The "Standard" Interviewer
Senior EngineerFocuses on core competencies, system constraints, and clear communication.
SimulateUnwritten Rules
Think Out Loud
Always explain your thought process before writing code or drawing architecture.