45 problems across 3 difficulty levels. Each includes a complete system design solution.
System design interview solution for Design URL Shortener. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
System design interview solution for Design WhatsApp. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design a search autocomplete/typeahead system using Trie data structures, prefix matching, and ranking.
System design interview solution for Design Uber. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design Spotify with audio streaming, playlist management, recommendation engine, offline downloads, and a global audio CDN.
Design a load balancer supporting L4/L7 routing, health checks, and multiple algorithms. Covers sticky sessions, SSL termination, and horizontal scaling.
Design a location-based service with geospatial indexing (QuadTree/GeoHash), proximity search, real-time location updates, and geofencing.
Design Instagram with photo upload pipeline, fan-out news feed, stories, and explore page. Covers image processing, CDN delivery, and feed ranking.
Design a Content Delivery Network with edge caching, cache invalidation, origin shield, and global traffic routing. Covers push vs pull CDN models.
Design a food delivery system (DoorDash/Uber Eats) with three-sided marketplace, order tracking, driver dispatch, and ETA calculation.
System design interview solution for Design Google Docs. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design a distributed job scheduler supporting cron-like scheduling, task queues, failure retry with backoff, and priority-based execution.
System design interview solution for Design Notification Service. Includes requirements, API design, data model, architecture, scaling strategy, and.
Design a parking garage system with OOP modeling, sensor integration, real-time space tracking, payment processing, and reservation management.
Design Google Maps with graph routing (Dijkstra/A*), tile rendering, real-time traffic, geocoding, and turn-by-turn navigation.
Design Tinder with geospatial matching, swipe queue generation, mutual like detection, and real-time chat. Covers GeoHash indexing and match algorithms.
Design a vending machine system with state machine modeling, inventory management, payment handling, and remote monitoring.
Design Zoom with WebRTC, SFU architecture, screen sharing, recording, and NAT traversal.
Design Facebook's social graph, news feed, friend suggestions, and notification system. Covers fan-out architecture, graph databases, and feed ranking.
Design a distributed cache with consistent hashing, eviction policies, replication, and cache invalidation. Covers Redis-like architecture at scale.
System design interview solution for Design Distributed Key-Value Store. Includes requirements, API design, data model, architecture, scaling strategy,.
Design Dropbox with file sync, chunking, deduplication, conflict resolution, and delta sync. Covers the sync protocol and metadata management.
Design Reddit with subreddits, voting (hot/top/controversial algorithms), threaded comment trees, and karma.
Design an authentication system with JWT vs sessions, OAuth2 flows, password hashing (bcrypt/argon2), MFA, and token refresh.
Design a ticket booking system (BookMyShow/Ticketmaster) with seat selection, temporary holds, concurrent booking prevention, and event management.
System design interview solution for Design Twitter. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design YouTube with video upload/transcoding pipeline, adaptive streaming, view counting, recommendations, and a global video CDN.
Design a UPI-like payment system with real-time payment flows, idempotency, settlement, and fraud detection. Covers NPCI architecture patterns.
Design a distributed web crawler with URL frontier, politeness policies, content deduplication, and distributed coordination.
Design a web search engine with crawling, indexing, PageRank, query processing, and result ranking.
Design a CI/CD deployment system with build pipelines, canary and blue-green deployments, automated rollback, and artifact management.
Design an e-commerce platform with product catalog, shopping cart, inventory management, checkout, and order processing.
System design interview solution for Design Netflix. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design an object storage system like S3 with erasure coding, metadata service, multi-tenancy, and 11 nines of durability.
Design TikTok with short video feed, recommendation algorithm, video upload/processing, and a global CDN.
Design a distributed lock service with consensus-based locking, fencing tokens, TTLs, and leader election. Covers Chubby/ZooKeeper architecture patterns.
Design Shopify as a multi-tenant SaaS e-commerce platform with storefront rendering, checkout, webhooks, and app ecosystem.
Design Airbnb with search (dates + location), booking system, pricing engine, and reviews.
Design a distributed message queue with topics, partitions, consumer groups, ordering guarantees, and at-least-once delivery.
Design a flight booking system with seat inventory, double-booking prevention, dynamic pricing, and GDS integration.
Design a collaborative code editor with real-time sync (CRDT/OT), code execution sandbox, syntax highlighting, and multi-cursor collaboration.
Design an analytics platform with event ingestion, real-time aggregation, dashboards, and ad-hoc queries. Covers Lambda architecture and columnar storage.
System design interview solution for Design Rate Limiter. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Design a digital wallet with balance management, P2P transfers, transaction history, and fraud detection.
System design interview solution for Design Payment System. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.