Low-Level Design: Pub/Sub Event System (OOP Interview)
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
System Design
System Design
System Design Interview: Design a Distributed Message Queue (Kafka)
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
System Design
Low-Level Design: Online Shopping Cart (OOP Interview)
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
Algorithms
Interval Algorithm Interview Patterns (2025)
6 min read Interval Algorithm Patterns Interval problems appear constantly in coding interviews — at Google, Meta, Airbnb, and Uber. The key skill: Read article
System Design
System Design Interview: Design a Social Media News Feed
6 min read System Design: News Feed (Facebook / Instagram / Twitter) A social media news feed aggregates posts from a user’s network Read article
Algorithms
Dynamic Programming on Strings: LCS, Edit Distance, and Patterns (2025)
6 min read Dynamic Programming on Strings String DP problems are among the most common in technical interviews, especially at Meta, Amazon, and Read article
System Design
Low-Level Design: Elevator System (OOP Interview)
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
Algorithms
Low-Level Design: Food Delivery System (OOP Interview)
9 min read Low-Level Design: Food Delivery System (OOP Interview) The food delivery system (DoorDash/Uber Eats style) is a rich OOP design problem Read article
Algorithms
Low-Level Design: Chat Application (OOP Interview)
8 min read Low-Level Design: Chat Application (OOP Interview) A chat application combines real-time messaging, user management, conversation threading, and notification delivery. It’s Read article
Algorithms
Graph Traversal Interview Patterns (2025)
9 min read Graph Traversal Interview Patterns (2025) Graph problems are among the most common in FAANG interviews — they appear as network Read article
Algorithms
Low-Level Design: Vending Machine (OOP Interview)
6 min read Low-Level Design: Vending Machine (OOP Interview) The vending machine is a classic state machine design question. It tests whether you Read article
Algorithms
Shortest Path Algorithm Interview Patterns (2025)
8 min read Shortest Path Algorithm Interview Patterns (2025) Shortest path problems are fundamental in graph interviews. Knowing when to apply BFS, Dijkstra, Read article
Algorithms
Low-Level Design: Tic-Tac-Toe Game (OOP Interview)
7 min read Low-Level Design: Tic-Tac-Toe Game Tic-Tac-Toe is a common LLD warm-up question that tests your ability to model game state, validate Read article
System Design
System Design Interview: Design Twitter / X Timeline
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
Algorithms
Low-Level Design: Movie Ticket Booking System (OOP Interview)
8 min read Low-Level Design: Movie Ticket Booking System The Movie Ticket Booking system (like BookMyShow or Fandango) is a popular LLD interview Read article