Twitter / X

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

Software Engineer • Coding • hard

Write a function to parse a massive log file of API requests and return the 99th percentile latency.

#Math #Sorting #Bucket Sort
Practice
Software Engineer • Coding • medium

Implement a thread-safe counter class for tracking tweet likes in a highly concurrent environment.

#Concurrency #Multithreading
Practice
Software Engineer • Coding • medium

Design a simplified version of Twitter. Implement functions to post a tweet, get the 10 most recent tweets in a news feed, follow a user, and unfollow a user.

#Hash Table #Heap #Object-Oriented Design
Practice
Software Engineer • Coding • hard

Given an array of k sorted arrays representing timelines from different users, merge them into a single sorted timeline.

#Heap #Divide and Conquer #Linked List
Practice
Software Engineer • Coding • medium

Implement a Token Bucket rate limiter class with an `allow_request(user_id)` method.

#Concurrency #Math #Design
Practice
Software Engineer • Coding • hard

Given a stream of tweets, find the top K most frequent hashtags in the last 5 minutes.

#Sliding Window #Heap #Queue
Practice
Software Engineer • Coding • medium

Find the shortest path (degrees of separation) between two users in a massive directed graph of followers.

#Graph #BFS #Bidirectional Search
Practice
Software Engineer • Coding • medium

Implement an LRU Cache to store the most recently accessed tweets.

#Hash Table #Doubly Linked List #Design
Practice
Software Engineer • Coding • easy

Given a string representing a tweet, calculate its length where URLs count as exactly 23 characters, regardless of their actual length.

#String #Parsing #Regex
Practice
Software Engineer • Coding • medium

Design an Autocomplete system for X handles. Implement `insert(handle)` and `search(prefix)`.

#Trie #String #Design
Practice
Software Engineer • Coding • easy

Given an array of tweet engagement scores (positive and negative integers), find the contiguous subarray with the maximum sum.

#Array #Dynamic Programming
Practice
Software Engineer • Coding • medium

Implement a sliding window algorithm to detect if a user has posted more than N tweets in the last M seconds.

#Queue #Sliding Window
Practice
Software Engineer • Coding • easy

Given a tree representing a tweet thread (replies to replies), write a function to find the maximum depth of the thread.

#Tree #DFS #BFS
Practice
Software Engineer • Coding • easy

You are given a list of user connections. Find the most influential user, defined as the user with the highest in-degree in the graph.

#Graph #Hash Table
Practice
Software Engineer • Coding • medium

Given a string, write a parser or state machine to extract all valid @mentions and #hashtags without using built-in regex libraries.

#String #State Machine
Practice

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Senior Engineer

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