Dashboard
Welcome!
Practice system design mock interviews.
Content Delivery & Media
Design Netflix
Design a video streaming service like Netflix that can handle 200M+ users globally with minimal buffering.
Design YouTube (Video Hosting & Streaming)
Design a video platform where users upload videos, which are then processed and delivered for streaming worldwide
Design Live Comments (FB Live / YouTube Live)
Design a system that streams live comments to users during events with millions of viewers
Social & Communication
Design Facebook Newsfeed
Design a system that generates a ranked, personalized feed of posts from friends and pages
Design Instagram (Image Sharing, Feed, Stories)
Design a social platform where users can post photos and videos, follow each other, and see a personalized feed
Design Twitter (Tweets, Timelines)
Design a microblogging service where users can post short messages and view timelines
Search & Discovery
Design Twitter/X Search (Real‑Time Indexing)
Design a system that indexes tweets in near real-time so they can be searched instantly
Design Yelp (Reviews + Search)
Design a platform where users can search for local businesses, view ratings, and post reviews
Design Web Crawler
Design a system to crawl the web, discovering, fetching, and storing billions of pages
Analytics, Metrics & Observability
Design Analytics Dashboard (Clickstream)
Design a system that collects user events from web and mobile apps, processes them in near real-time, and displays aggregated metrics on dashboards
Design Distributed Logging & Monitoring
Design a centralized system that collects logs and metrics from thousands of services
Design Trending Hashtags / Top‑K
Design a system that computes the most popular hashtags or topics over sliding time windows
Storage Systems
Design Cloud Storage & Sync
Design a cloud storage service that lets users save files, sync them across devices, and share them with others
Design Distributed Key‑Value Store
Design a distributed key-value store that can handle massive amounts of reads and writes while offering tunable consistency
Counters, Notifications & Growth Infra
Design Facebook Likes (Distributed Counter)
Design a counter system to track likes or reactions for posts with potentially billions of interactions
Design Global Notification Service
Design a notification platform that can deliver messages across channels like email, SMS, and push notifications
Scheduling, Control & Governance
Design Job Scheduler (Distributed Cron)
Design a system that allows scheduling jobs to run at specific times across a distributed cluster
Design API Rate Limiter
Design a system to enforce quotas and rate limits for API clients
Transactions, Commerce & Reservations
Design Ticketmaster (Seat Reservations)
Design a ticketing system that allows users to view events, select seats, and purchase tickets
Design Short URL Service (TinyURL/Bit.ly)
Design a service that takes a long URL and returns a shortened alias that can be shared easily
Design Booking System (Inventory + Reservations)
Design a booking system for hotels or properties where users can search for availability and make reservations
Realtime & Stream Processing
Design Distributed Queue (Kafka/RabbitMQ)
Design a messaging system where producers and consumers communicate asynchronously
Design Uber Backend (Dispatch & Matching)
Design the backend system for a ride-hailing platform that matches riders with drivers in real time
