Low-Level Design: Vending Machine (OOP Design Interview)
6 min read Low-Level Design: Vending Machine (OOP Design Interview) The vending machine is a classic low-level design problem that tests State Pattern, […] Read article
System Design
System Design
System Design Interview: Design Google Search Autocomplete (Typeahead)
6 min read System Design Interview: Design Google Search Autocomplete (Typeahead) Search autocomplete (typeahead) is one of the most common system design questions, Read article
System Design
System Design Interview: API Rate Limiter Deep Dive (All Algorithms)
8 min read System Design Interview: Design an API Rate Limiter (Deep Dive) API rate limiting is a fundamental system design topic — Read article
Algorithms
Monotonic Stack Patterns: Complete Interview Guide (2025)
8 min read Monotonic Stack Patterns: Complete Interview Guide Monotonic stacks solve a specific family of problems related to “nearest greater/smaller element” queries Read article
System Design
System Design Interview: Design a Hotel Booking System (Airbnb)
9 min read System Design Interview: Design a Hotel Booking System (Airbnb/Booking.com) Hotel booking systems are canonical system design problems testing inventory management, Read article
System Design
System Design Interview: Design a Payment System (Stripe/PayPal)
9 min read System Design Interview: Design a Payment System (Stripe/PayPal) Payment system design is one of the most important system design interviews, Read article
System Design
System Design Interview: Design Google Maps / Navigation System
7 min read System Design Interview: Design Google Maps / Navigation System Designing a mapping and navigation system like Google Maps is a Read article
Algorithms, System Design
Database Indexing and Query Optimization Interview Guide
5 min read Database Indexing and Query Optimization for Interviews Database indexing questions appear frequently in system design interviews and sometimes as standalone Read article
System Design
Low-Level Design: Elevator System (OOP Design Interview)
6 min read Elevator System Low-Level Design Designing an elevator system is a classic low-level design (LLD) interview question asked at companies like Read article
System Design
System Design Interview: Design a Chat Application (WhatsApp)
4 min read System Design Interview: Design a Chat Application (WhatsApp) Designing a real-time messaging application like WhatsApp is a comprehensive system design Read article
Algorithms
Design Patterns in Python for Coding Interviews (2025)
4 min read Design Patterns in Python for Coding Interviews (2025) Python-specific design pattern implementations come up in senior coding rounds at Stripe, Read article
System Design
Low-Level Design Interview: Design a Parking Lot System
4 min read Low-Level Design: Design a Parking Lot System Parking lot is a classic Low-Level Design (LLD) / Object-Oriented Design interview question Read article
Algorithms
Trie Interview Patterns: Autocomplete, Word Search, and Prefix Problems (2025)
4 min read Trie Interview Patterns: Autocomplete, Word Search, and Prefix Problems (2025) Tries (prefix trees) are the go-to data structure for string Read article
System Design
System Design Interview: How DNS Works and How to Design It
3 min read System Design Interview: How DNS Works and How to Design It Understanding DNS (Domain Name System) is fundamental to backend Read article
System Design
System Design Interview: Design a Pastebin / Code Snippet Service
6 min read System Design Interview: Design a Pastebin / Code Snippet Service Designing Pastebin is a classic beginner-to-intermediate system design question that Read article