High-Level Design
20 system design questions frequently asked at top tech companies. Each includes key components, approach steps, and requirements breakdown.
Design a URL Shortener (like bit.ly)
Design a system that takes long URLs and creates short, unique aliases that redirect to the original URL.
Design a Rate Limiter
Design a distributed rate limiting service that controls the rate of API requests to protect backend services.
Design a Notification System
Design a scalable notification system that delivers push, SMS, and email notifications reliably.
Design Typeahead / Autocomplete
Design a real-time autocomplete system that suggests search queries as the user types.
Design a Web Crawler
Design a distributed web crawler that efficiently discovers, fetches, and processes billions of web pages.
Design Twitter / Social Media Feed
Design a social media platform where users can post tweets, follow others, and see a personalized timeline.
Design Instagram / Photo Sharing Platform
Design a photo and video sharing platform where users can upload, view, and interact with media content.
Design a News Feed System
Design the backend for a social media news feed that aggregates and ranks posts from followed users and pages.
Design Netflix / Video Streaming Platform
Design a video streaming service that delivers on-demand content to millions of concurrent users worldwide.
Design YouTube / Video Platform
Design a video sharing platform where users can upload, transcode, search, and stream videos at scale.
Design WhatsApp / Chat Messaging System
Design a real-time messaging platform that supports one-on-one and group messaging with delivery guarantees.
Design Uber / Ride Sharing Service
Design a ride-sharing platform that matches riders with nearby drivers in real time.
Design a Payment System (Stripe/PayPal)
Design a payment processing platform that handles transactions, refunds, and settlements reliably.
Design an E-Commerce Platform (Amazon)
Design a large-scale e-commerce platform with product catalog, cart, checkout, and order management.
Design Dropbox / File Storage & Sync
Design a cloud file storage service that allows users to store, sync, and share files across devices.
Design a Distributed Cache (Redis)
Design a distributed in-memory caching system that provides low-latency data access across a cluster.
Design a Message Queue (Kafka)
Design a distributed message queue system that provides reliable, ordered, and scalable message delivery.
Design Google Search
Design a web search engine that crawls, indexes, and ranks billions of web pages to answer user queries.
Design Real-time Collaboration (Google Docs)
Design a real-time collaborative document editing system where multiple users can edit the same document simultaneously.
Design a Ticketing System (BookMyShow/Ticketmaster)
Design an online ticket booking platform for movies, concerts, and events with seat selection and payment.