Case Studies
Real-world system designs from top companies
Design a Chat System
A real-time chat system supports 1:1 conversations, group chats, message ordering, offline delivery, and read receipts. Whether it is Slack, Discord, or a ...
Design Dropbox: A Cloud File Storage and Sync System
Dropbox synchronizes files across billions of devices, storing over 1 exabyte of data for 700+ million users. Designing a system like Dropbox tests your un...
Design an E-Commerce Platform
An e-commerce platform like Amazon handles hundreds of millions of products, processes millions of orders daily, and must provide a seamless shopping exper...
Design Google Search: A Web Search Engine
Google Search handles over 8.5 billion queries per day, indexing hundreds of billions of web pages and returning results in under 500 milliseconds. Designi...
Design Instagram: A Photo-Sharing Social Platform
Instagram serves over 2 billion monthly active users, handling photo uploads, news feed generation, stories, and social interactions at massive scale. This...
Design Netflix: A Video Streaming Architecture
Netflix serves over 260 million subscribers across 190+ countries, streaming billions of hours of content monthly. Its architecture is a masterclass in mic...
Design a News Feed System
A news feed is the core feature of most social media platforms — Facebook, Instagram, Twitter, and LinkedIn all depend on a well-designed feed. The news fe...
Design a Notification System
A notification system is a critical component of virtually every modern application. It delivers timely information to users through multiple channels — pu...
Design a Payment System
A payment system is one of the most critical components of any e-commerce or fintech platform. It handles money — making correctness, security, and reliabi...
Design a Ride Sharing System
A ride sharing system like Lyft or Ola connects riders with drivers using real-time geospatial matching. While similar to Uber (covered in a separate case ...
Design Twitter: A Social Media Microblogging Platform
Twitter (now X) processes hundreds of millions of tweets daily and serves billions of timeline reads. It is a classic system design interview question beca...
Design Uber: A Ride-Hailing Platform
Uber connects millions of riders with drivers in real-time across 10,000+ cities worldwide. Designing Uber is one of the most challenging system design pro...
Design a URL Shortener (like TinyURL / Bitly)
A URL shortener converts long URLs into compact, shareable links. This is one of the most commonly asked system design interview questions because it touch...
Design WhatsApp: A Real-Time Messaging System
WhatsApp is one of the most widely used messaging platforms, handling over 100 billion messages per day across 2+ billion users. Designing a system like Wh...
Design YouTube: A Video Streaming Platform
YouTube is the world's largest video-sharing platform, serving over 1 billion hours of video daily to 2+ billion users. Designing YouTube tests your knowle...