Sliding Window Interview Patterns: A Complete Guide (2025)
8 min read The Sliding Window Technique The sliding window technique optimizes brute-force O(n^2) or O(n^3) problems to O(n) by maintaining a window […] Read article
Algorithms
System Design
System Design Interview: Distributed Lock Manager (Redis / Zookeeper)
8 min read Why Distributed Locks Are Needed In a distributed system, multiple instances of a service may run concurrently. When these instances Read article
System Design
System Design Interview: Stock Exchange (NYSE / Nasdaq Order Book)
8 min read What Makes Stock Exchanges Hard to Design A stock exchange is one of the most demanding distributed systems: it must Read article
Algorithms
Heap and Priority Queue Interview Patterns (2025)
8 min read Heap Fundamentals A heap is a complete binary tree satisfying the heap property: in a min-heap, every parent is smaller Read article
System Design
System Design Interview: Content Moderation System (Instagram / YouTube)
8 min read Why Content Moderation Is a Hard Systems Problem A platform with 500 million daily active users generates billions of pieces Read article
Algorithms
Linked List Interview Patterns: A Complete Guide (2025)
8 min read Why Linked Lists Are Tested Linked lists appear in roughly 10% of coding interviews, mostly testing pointer manipulation, two-pointer techniques, Read article
System Design
System Design Interview: Analytics Platform (ClickHouse / Snowflake Scale)
7 min read Analytics vs Transactional Systems OLTP (Online Transaction Processing) systems like PostgreSQL are optimized for short, frequent reads and writes to Read article
System Design
System Design Interview: API Gateway (Kong / AWS API Gateway)
8 min read What Is an API Gateway? An API gateway is the single entry point for all client requests to a microservices Read article
System Design
System Design Interview: Recommendation System (Netflix / Spotify)
8 min read Why Recommendations Matter Netflix reports that 80% of content watched is discovered through recommendations. Spotify generates 30% of its streams Read article
System Design
System Design Interview: Hotel Booking System (Airbnb / Booking.com)
8 min read Problem Overview Design a hotel or short-term rental booking system like Airbnb or Booking.com. Users search for available properties in Read article
Algorithms
Binary Search Interview Patterns: A Complete Guide (2025)
9 min read Why Binary Search Is Tested So Frequently Binary search appears in roughly 10-15% of FAANG coding interviews, both as a Read article
System Design
System Design Interview: Payment Processing System (Stripe / PayPal)
8 min read Why Payment Systems Are Hard Payment systems are among the hardest distributed systems to design because money movement requires exactly-once Read article
System Design
System Design Interview: Location-Based Service (Yelp / Google Maps)
8 min read Problem Overview Design a location-based service that allows users to find nearby businesses (Yelp) or navigate between locations (Google Maps). Read article
System Design
System Design Interview: File Storage Service (Dropbox / Google Drive)
7 min read Problem Overview Design a file storage and sync service like Dropbox or Google Drive. Users can upload files up to Read article
Algorithms
Dynamic Programming Interview Patterns: A Complete Guide (2025)
8 min read What Is Dynamic Programming? Dynamic programming (DP) solves problems by breaking them into overlapping subproblems, solving each subproblem once, and Read article