Low Level Design: Real-Time Messaging Service
4 min read What Is a Real-Time Messaging Service? A real-time messaging service is the transport layer that moves data from one endpoint […] 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
Low Level Design: Message Delivery Receipts Service
5 min read What Is a Message Delivery Receipts Service? A message delivery receipts service tracks the lifecycle of every message from send Read article
System Design
Low Level Design: Plan Management Service
4 min read What Is a Plan Management Service? A Plan Management Service owns the catalog of subscription plans and the logic for Read article
System Design
Low Level Design: Usage Metering Service
5 min read What Is a Usage Metering Service? A Usage Metering Service measures how much of a resource a customer consumes, aggregates Read article
System Design
Low Level Design: Semantic Search Service
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System Design
Low Level Design: Leaderboard Service
4 min read What Is a Leaderboard Service? A leaderboard service ranks users or entities by a numeric score and exposes that ranking Read article
System Design
Low Level Design: Ranking System
4 min read What Is a Ranking System? A ranking system assigns ordinal positions to entities (users, products, documents, players) based on one Read article
System Design
Low Level Design: Scoring Service
5 min read What Is a Scoring Service? A scoring service is the write-side component responsible for receiving raw score events, applying business Read article
System Design
Low Level Design: Config Management Service
4 min read What Is a Config Management Service? A Config Management Service (CMS) centralizes application configuration so that services can retrieve settings Read article
System Design
Low Level Design: Cross-Datacenter Sync Service
4 min read What Is a Cross-Datacenter Sync Service? A cross-datacenter sync service coordinates state between two or more physical data centers that Read article
System Design
Low Level Design: Global Database Design
5 min read What Is a Global Database Design? A globally distributed database serves reads and writes from multiple geographic regions while providing Read article
System Design
Low Level Design: File Upload Service
4 min read What Is a File Upload Service? A file upload service provides a reliable, scalable mechanism for clients to transfer files Read article
System Design
Low Level Design: Chunked Upload Service
5 min read What Is a Chunked Upload Service? A chunked upload service splits a large file into fixed-size pieces and transfers them Read article
System Design
Low Level Design: Resumable Upload Protocol
6 min read What Is a Resumable Upload Protocol? A resumable upload protocol allows an interrupted file transfer to continue from the exact Read article
System Design
Low Level Design: Digest Email Service
6 min read What Is a Digest Email Service? A Digest Email Service batches individual notification events that would otherwise generate separate emails Read article