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.
Solve the Uber system design interview: real-time location updates, driver matching, geospatial indexing, trip state, pricing, scale, 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.
Solve the Google Docs system design interview: real-time editing, operational transform or CRDTs, presence, storage, permissions, and scaling 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.
Solve the Zoom system design interview: WebRTC, SFU media routing, meeting control plane, screen sharing, recording, NAT traversal, and scaling.
Design Facebook's social graph, news feed, friend suggestions, and notification system. Covers fan-out architecture, graph databases, and feed ranking.
Solve the distributed cache system design interview: cache API, consistent hashing, replication, eviction, invalidation, hot keys, and scaling tradeoffs.
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.
Solve the ticket booking system design interview: seat maps, temporary holds, concurrency control, payment flow, queues, scaling, and tradeoffs.
System design interview solution for Design Twitter. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.
Solve the YouTube system design interview: video upload, transcoding pipeline, object storage, CDN streaming, view counts, recommendations, and scale.
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.
Solve the code deployment system design interview: build pipelines, artifact storage, canary releases, blue-green deploys, rollback, and observability.
Design an e-commerce system for interviews: product catalog, search, cart, checkout, inventory reservations, payments, order workflow, scaling, and tradeoffs.
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.
Solve the TikTok system design interview: video upload, transcoding, feed ranking, recommendations, CDN delivery, social graph, and scaling tradeoffs.
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.
Solve the rate limiter system design interview: token bucket, sliding window, Redis counters, distributed limits, API gateway placement, and tradeoffs.
Design a digital wallet with balance management, P2P transfers, transaction history, and fraud detection.
Design a payment system for interviews: payment flow, idempotency keys, ledger data model, retries, reconciliation, fraud checks, scaling, and tradeoffs.