Dashboard

Welcome!

Practice system design mock interviews.

Loading ...

Content Delivery & Media

Design Netflix

No Login Required

Design a video streaming service like Netflix that can handle 200M+ users globally with minimal buffering.

Netflix
Medium

Design YouTube (Video Hosting & Streaming)

Design a video platform where users upload videos, which are then processed and delivered for streaming worldwide

GoogleYouTube
Medium

Design Live Comments (FB Live / YouTube Live)

Design a system that streams live comments to users during events with millions of viewers

MetaYouTube
Hard

Social & Communication

Design Facebook Newsfeed

Design a system that generates a ranked, personalized feed of posts from friends and pages

Meta
Hard

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

Meta
Medium

Design Twitter (Tweets, Timelines)

Design a microblogging service where users can post short messages and view timelines

Twitter
Medium

Search & Discovery

Design Twitter Search (Real‑Time Indexing)

Design a system that indexes tweets in near real-time so they can be searched instantly

Twitter
Hard

Design Yelp (Reviews + Search)

Design a platform where users can search for local businesses, view ratings, and post reviews

YelpGoogle
Medium

Design Web Crawler

Design a system to crawl the web, discovering, fetching, and storing billions of pages

Google
Hard

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

Google
Hard

Design Distributed Logging & Monitoring

Design a centralized system that collects logs and metrics from thousands of services

GoogleMeta
Hard

Design Trending Hashtags / Top‑K

Design a system that computes the most popular hashtags or topics over sliding time windows

TwitterMeta
Medium

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

DropboxGoogle
Hard

Design Distributed Key‑Value Store

Design a distributed key-value store that can handle massive amounts of reads and writes while offering tunable consistency

GoogleAmazon
Hard

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

Meta
Medium

Design Global Notification Service

Design a notification platform that can deliver messages across channels like email, SMS, and push notifications

AmazonPinterest
Medium

Scheduling, Control & Governance

Design Job Scheduler (Distributed Cron)

Design a system that allows scheduling jobs to run at specific times across a distributed cluster

GoogleNetflix
Medium

Design API Rate Limiter

Design a system to enforce quotas and rate limits for API clients

StripeAmazon
Medium

Transactions, Commerce & Reservations

Design Ticketmaster (Seat Reservations)

Design a ticketing system that allows users to view events, select seats, and purchase tickets

TicketmasterAmazon
Hard

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

AmazonTwitter
Easy

Design Booking System (Inventory + Reservations)

Design a booking system for hotels or properties where users can search for availability and make reservations

ExpediaAirbnb
Medium

Realtime & Stream Processing

Design Distributed Queue (Kafka/RabbitMQ)

Design a messaging system where producers and consumers communicate asynchronously

AmazonApple
Medium

Design Uber Backend (Dispatch & Matching)

Design the backend system for a ride-hailing platform that matches riders with drivers in real time

Uber
Hard