System Design

⏱ 6 min read Low-Level Design: Logging Framework A logging framework is a fundamental software engineering tool — and a frequently-asked OOP design question […] Read article

⏱ 6 min read System Design: Distributed Search Engine A distributed search engine indexes documents and serves queries with sub-100ms latency at massive scale. Read article

⏱ 8 min read Low-Level Design: Notification System A notification system delivers messages to users via multiple channels (push, email, SMS, in-app). It must Read article

⏱ 7 min read Low-Level Design: Task Scheduler / Job Queue A task scheduler executes jobs at specified times or with specified delays, tracks Read article

⏱ 6 min read System Design: Distributed Message Queue (Kafka) A distributed message queue decouples producers (services that generate events) from consumers (services that Read article

⏱ 6 min read Low-Level Design: Pub/Sub Event System The Publish-Subscribe pattern is one of the most important OOP design patterns. It decouples event Read article

⏱ 7 min read Low-Level Design: Online Shopping Cart The online shopping cart is a fundamental e-commerce OOP design problem. It tests entity modeling Read article

⏱ 6 min read System Design: News Feed (Facebook / Instagram / Twitter) A social media news feed aggregates posts from a user’s network Read article

⏱ 6 min read Low-Level Design: Elevator System The elevator system is a classic OOP interview problem testing state machines, dispatching algorithms, and clean Read article

⏱ 8 min read System Design Interview: Design Twitter / X Timeline Designing Twitter’s home timeline is one of the most-cited system design interview Read article

⏱ 9 min read System Design Interview: Design WhatsApp / Real-Time Messaging Designing a real-time messaging system like WhatsApp or iMessage is a top-tier Read article

⏱ 8 min read System Design Interview: Design YouTube / Video Streaming Platform Designing YouTube is one of the most comprehensive system design problems Read article

⏱ 7 min read System Design Interview: Design Instagram / Photo Sharing Platform Designing Instagram tests your knowledge of media storage, feed generation, CDN Read article

⏱ 7 min read Database Sharding: Complete System Design Guide Database sharding is the technique of horizontally partitioning data across multiple database instances (shards). Read article

⏱ 10 min read Low-Level Design: Library Management System (OOP Interview) The Library Management System is a comprehensive LLD interview problem testing your ability Read article