System Design Interview: Design a Content Delivery Network (CDN)
What Is a CDN? A Content Delivery Network is a globally distributed network of edge servers (Points of Presence, PoPs) […]
System Design
System Design
System Design Interview: Design a Real-Time Bidding (RTB) System
What Is Real-Time Bidding? Real-Time Bidding (RTB) is the programmatic auction mechanism behind most digital display advertising. When a user
Algorithms
Tree Interview Patterns: DFS, BFS, LCA, BST, Tree DP, Serialization
Tree Interview Patterns Trees appear in nearly every software engineering interview. Mastering the core traversal patterns and recognizing which technique
System Design
System Design Interview: Microservices and Service Mesh (Envoy, Istio, mTLS)
What Is a Service Mesh? A service mesh is an infrastructure layer that handles service-to-service communication in a microservices architecture.
System Design
System Design Interview: Design a Location-Based Services System (Yelp/Google Maps)
What Is a Location-Based Services System? A location-based services (LBS) system enables geospatial queries: find nearby restaurants, show points of
Algorithms
1D Dynamic Programming Interview Patterns: House Robber, LIS, Coin Change, Word Break
1D Dynamic Programming Interview Patterns 1D DP problems have a state space that reduces to a single index or value.
System Design
System Design Interview: Design a Task Scheduling System (Cron/Airflow)
What Is a Task Scheduling System? A task scheduling system triggers jobs at specified times or on recurring schedules. Examples:
Algorithms
Graph BFS and DFS Interview Patterns: Islands, Shortest Path, Cycle Detection
Graph BFS and DFS Interview Patterns Graph traversal is one of the most tested interview topics. BFS (Breadth-First Search) and
System Design
System Design Interview: Design a Real-Time Chat Application (WhatsApp/Slack)
What Is a Real-Time Chat System? A real-time chat system enables persistent messaging between users with delivery guarantees and online
Algorithms
Trie (Prefix Tree) Interview Patterns: Autocomplete, Word Search, Wildcard
Trie (Prefix Tree) Interview Patterns A Trie (prefix tree) is a tree where each node represents a character in a
System Design
System Design Interview: Design a Configuration Management System (etcd/Consul)
What Is a Configuration Management System? A configuration management system stores key-value configuration data that services read at startup or
System Design
System Design Interview: Design a Search Engine (Query Processing and Ranking)
What Is a Search Engine? A search engine indexes a corpus of documents and retrieves the most relevant results for
System Design
System Design Interview: Design a Fraud Detection System
What Is a Fraud Detection System? A fraud detection system identifies and blocks fraudulent transactions, account takeovers, and abuse in
System Design
System Design Interview: Design a Digital Wallet and Payment System
What Is a Digital Wallet? A digital wallet stores funds and enables transfers between users and merchants. Examples: PayPal, Venmo,
System Design
System Design Interview: Design a Video Streaming Platform (YouTube/Netflix)
What Is a Video Streaming Platform? A video streaming platform stores, processes, and delivers video content to millions of concurrent