Design a Distributed ID Generator (Snowflake)
4 min read Design a distributed ID generation service. Every large-scale system needs unique IDs — for database rows, events, messages, and transactions. […] Read article
System Design
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System Design
Learn to design scalable, reliable systems that handle millions of users. System design interviews test your ability to architect real-world applications, considering tradeoffs, scalability, and best practices.
Core Topics:
Scalability: Load balancing, horizontal vs vertical scaling
Storage: Databases (SQL vs NoSQL), caching (Redis, Memcached)
Reliability: Replication, failover, disaster recovery
Performance: CDNs, caching strategies, database indexing
Common Design Questions:
Design URL shortener (bit.ly)
Design rate limiter
Design Twitter/Instagram feed
Design messaging system (WhatsApp)
Design file storage (Dropbox)
Interview Level: Senior engineers (L5+) at FAANG companies. Requires 3-5+ years experience to tackle effectively.
Preparation: Study system design patterns, understand distributed systems fundamentals, and practice mock interviews.
System Design
Design Google Maps / Navigation System
6 min read Design a navigation system like Google Maps. This problem combines geospatial data at scale, graph algorithms, real-time data ingestion, and Read article
System Design
Design a Hotel / Airbnb Reservation System
5 min read Design a hotel or vacation rental reservation system like Booking.com or Airbnb. The core challenge isn’t the search UI — Read article
System Design
Design a Proximity Service (Yelp / Nearby Search)
5 min read Design a proximity service like Yelp’s “restaurants near me” or Google Maps’ nearby search. The core challenge is geospatial indexing Read article
System Design
Design a Payment System
5 min read Design a payment system like Stripe, PayPal, or an internal payments platform at a company like Uber or Amazon. This Read article
System Design
Design a Distributed Key-Value Store
5 min read Design a distributed key-value store like DynamoDB, Cassandra (its KV layer), or Redis Cluster. This is one of the most Read article
System Design
Design a News Feed (Facebook-style)
4 min read Design a news feed system like Facebook’s. This is a richer problem than the Twitter feed design — Facebook’s feed Read article
System Design
Design a Web Crawler
5 min read Design a web crawler that can index a significant portion of the internet. This question tests whether you understand distributed Read article
System Design
Design Dropbox / Google Drive
5 min read Design a file storage and sync service like Dropbox or Google Drive. This problem tests your ability to handle large Read article
System Design
System Design: Search Autocomplete (Google Typeahead)
6 min read Search autocomplete — the suggestions that appear as you type into Google, Amazon, or YouTube — is a deceptively interesting Read article
System Design
System Design: Notification System (Push, Email, SMS)
6 min read A notification system is asked at almost every senior system design interview because it surfaces real architectural challenges: fanout at Read article
System Design
System Design: Ride-Sharing App (Uber / Lyft)
6 min read Designing a ride-sharing app is a rich system design problem that tests your ability to handle real-time location data, geospatial Read article
System Design
System Design: YouTube / Video Streaming Platform
6 min read Video streaming is one of the most infrastructure-intensive system design problems. YouTube streams 1 billion hours of video per day. Read article
System Design
System Design: Twitter / Social Media Feed
6 min read Designing a social media feed is one of the most nuanced system design problems you’ll encounter in interviews. It looks Read article
System Design
System Design: Chat System (WhatsApp / Messenger Scale)
7 min read A chat system is a perennial system design interview question. It requires you to reason about real-time communication, persistent storage, Read article