System Design Interview: Web Crawler (Google Search Indexing)
8 min read What Is a Web Crawler? A web crawler (spider) systematically browses the web, downloading pages and extracting links to discover […] Read article
System Design
System Design
System Design Interview: Content Delivery Network (CDN)
7 min read What Is a CDN? A Content Delivery Network is a globally distributed network of servers (Points of Presence, or PoPs) Read article
System Design
System Design Interview: Real-Time Collaboration (Google Docs)
7 min read The Core Challenge Real-time collaborative editing requires multiple users to edit the same document simultaneously and see each other changes Read article
System Design
System Design Interview: Search Autocomplete / Typeahead (2025)
7 min read What Is a Typeahead System? A typeahead (search autocomplete) system returns a ranked list of query completions as the user Read article
System Design
System Design Interview: Gaming Leaderboard and Matchmaking System
8 min read Problem Overview Design a leaderboard and matchmaking system for a multiplayer game with 50 million players. The leaderboard shows global Read article
System Design
System Design Interview: IoT Platform (Connected Devices at Scale)
8 min read IoT system design is increasingly common at Amazon (AWS IoT), Google (Cloud IoT), Tesla, Nest, and any company building connected Read article
Algorithms
SRE and DevOps Interview Questions: SLOs, On-Call, and Incident Response (2025)
9 min read Site Reliability Engineering (SRE) and DevOps interviews mix system design, operations knowledge, and cultural questions. Google, Netflix, Uber, and most Read article
System Design
System Design Interview: Ad Serving System (Google Ads / Meta Ads)
9 min read Ad serving is at the core of Google and Meta businesses and is one of the highest-stakes systems in the Read article
System Design
System Design Interview: Food Delivery App (DoorDash / UberEats)
8 min read Food delivery is a three-sided marketplace connecting customers, restaurants, and delivery drivers — more complex than ride-sharing because orders involve Read article
Algorithms
REST API Design Best Practices: Versioning, Pagination, and Error Handling
8 min read API design questions appear in backend, platform engineering, and staff-level interviews. A poorly designed API is a permanent liability — Read article
System Design
System Design Interview: Ticketing System (Ticketmaster / Concert Tickets)
8 min read Ticketing systems for concerts and sports events are famous for their demand spikes: a Taylor Swift concert sells 50,000 tickets Read article
Algorithms
Object-Oriented Design Interview Questions: Parking Lot, Library, and More
9 min read Object-oriented design (OOD) questions test whether you can translate real-world requirements into clean class hierarchies. Amazon, Uber, and Microsoft frequently Read article
System Design
System Design Interview: Live Streaming Platform (Twitch)
8 min read Designing a live streaming platform is fundamentally different from designing video-on-demand (YouTube). The challenge is latency — live content must Read article
Algorithms
Kotlin Interview Questions: Coroutines, Extension Functions, and Android (2025)
7 min read Kotlin is the primary language for Android development and is increasingly used for backend services (Ktor, Spring Boot). Kotlin interviews Read article
System Design
System Design Interview: Email System at Gmail Scale
7 min read Designing an email system is a favorite at Google (who built Gmail) and at companies that rely heavily on transactional Read article