Dynamic Programming Interview Patterns: A Complete Guide (2025)
What Is Dynamic Programming? Dynamic programming (DP) solves problems by breaking them into overlapping subproblems, solving each subproblem once, and […]
Algorithms
System Design
System Design Interview: File Storage Service (Dropbox / Google Drive)
Problem Overview Design a file storage and sync service like Dropbox or Google Drive. Users can upload files up to
System Design
System Design Interview: Real-Time Collaboration (Google Docs)
The Core Challenge Real-time collaborative editing requires multiple users to edit the same document simultaneously and see each other changes
System Design
System Design Interview: Content Delivery Network (CDN)
What Is a CDN? A Content Delivery Network is a globally distributed network of servers (Points of Presence, or PoPs)
System Design
System Design Interview: Gaming Leaderboard and Matchmaking System
Problem Overview Design a leaderboard and matchmaking system for a multiplayer game with 50 million players. The leaderboard shows global
System Design
System Design Interview: Search Autocomplete / Typeahead (2025)
What Is a Typeahead System? A typeahead (search autocomplete) system returns a ranked list of query completions as the user
System Design
System Design Interview: Ad Serving System (Google Ads / Meta Ads)
Ad serving is at the core of Google and Meta businesses and is one of the highest-stakes systems in the
Algorithms
SRE and DevOps Interview Questions: SLOs, On-Call, and Incident Response (2025)
Site Reliability Engineering (SRE) and DevOps interviews mix system design, operations knowledge, and cultural questions. Google, Netflix, Uber, and most
System Design
System Design Interview: IoT Platform (Connected Devices at Scale)
IoT system design is increasingly common at Amazon (AWS IoT), Google (Cloud IoT), Tesla, Nest, and any company building connected
System Design
System Design Interview: Ticketing System (Ticketmaster / Concert Tickets)
Ticketing systems for concerts and sports events are famous for their demand spikes: a Taylor Swift concert sells 50,000 tickets
Algorithms
REST API Design Best Practices: Versioning, Pagination, and Error Handling
API design questions appear in backend, platform engineering, and staff-level interviews. A poorly designed API is a permanent liability —
System Design
System Design Interview: Food Delivery App (DoorDash / UberEats)
Food delivery is a three-sided marketplace connecting customers, restaurants, and delivery drivers — more complex than ride-sharing because orders involve
Algorithms
Kotlin Interview Questions: Coroutines, Extension Functions, and Android (2025)
Kotlin is the primary language for Android development and is increasingly used for backend services (Ktor, Spring Boot). Kotlin interviews
System Design
System Design Interview: Live Streaming Platform (Twitch)
Designing a live streaming platform is fundamentally different from designing video-on-demand (YouTube). The challenge is latency — live content must
Algorithms
Object-Oriented Design Interview Questions: Parking Lot, Library, and More
Object-oriented design (OOD) questions test whether you can translate real-world requirements into clean class hierarchies. Amazon, Uber, and Microsoft frequently