System Design Interview: Design a Distributed File System (HDFS / GFS)
5 min read What Is a Distributed File System? A distributed file system (DFS) stores files across many machines, exposing them as a […] Read article
System Design
System Design
System Design Interview: Design a Metrics and Monitoring System (Prometheus)
5 min read What Is a Metrics and Monitoring System? A metrics system collects numerical measurements from services (request rate, error rate, latency, Read article
System Design
System Design Interview: Design an E-commerce Checkout System
5 min read What Is an E-commerce Checkout System? The checkout system orchestrates the final steps of an online purchase: cart validation, inventory Read article
System Design
System Design Interview: Design an Object Storage System (Amazon S3)
5 min read What Is an Object Storage System? Object storage (Amazon S3, Google Cloud Storage) stores arbitrary-size files (objects) in named buckets. Read article
System Design
System Design Interview: Design a Payment Processing System
5 min read What Is a Payment Processing System? A payment processing system moves money from a buyer to a seller by orchestrating Read article
Algorithms
Sorting Algorithm Interview Patterns: Quicksort, Merge Sort, Counting Sort, Custom Sort
5 min read Sorting Algorithm Interview Patterns While most interviews don’t ask you to implement sorting from scratch, understanding the algorithms helps you Read article
System Design
System Design Interview: Design a Social Graph (Friend Connections)
5 min read What Is a Social Graph? A social graph represents relationships between users: friendships (Facebook), follow relationships (Twitter/Instagram), professional connections (LinkedIn). Read article
System Design
System Design Interview: Design a Hotel / Booking Reservation System
5 min read What Is a Hotel Reservation System? A hotel reservation system lets users search for available rooms, make reservations with guaranteed Read article
System Design
System Design Interview: Design a Key-Value Store (Redis / DynamoDB)
5 min read What Is a Distributed Key-Value Store? A key-value store maps arbitrary keys to values with O(1) average operations. Distributed key-value Read article
System Design
System Design Interview: Design a Stock Exchange / Trading System
5 min read What Is a Stock Exchange System? A stock exchange matching engine pairs buy and sell orders in real time, executing Read article
System Design
System Design Interview: Design Google Docs / Collaborative Editing
5 min read What Is Collaborative Document Editing? Real-time collaborative editing allows multiple users to simultaneously edit the same document, with changes from Read article
System Design
System Design Interview: Design a Database Connection Pool
5 min read What Is a Database Connection Pool? Opening a database connection is expensive: TCP handshake, authentication, SSL negotiation, session setup — Read article
System Design
System Design Interview: Design a Content Delivery Network (CDN)
5 min read What Is a CDN? A Content Delivery Network is a globally distributed network of edge servers (Points of Presence, PoPs) Read article
Algorithms
Tree Interview Patterns: DFS, BFS, LCA, BST, Tree DP, Serialization
5 min read Tree Interview Patterns Trees appear in nearly every software engineering interview. Mastering the core traversal patterns and recognizing which technique Read article
System Design
System Design Interview: Design a Real-Time Bidding (RTB) System
5 min read What Is Real-Time Bidding? Real-Time Bidding (RTB) is the programmatic auction mechanism behind most digital display advertising. When a user Read article