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SDMastery

hard Problems

12 problems at hard level.

hard

Design Uber

System design interview solution for Design Uber. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.

9 min read
hard

Design a Location-Based Service

Design a location-based service with geospatial indexing (QuadTree/GeoHash), proximity search, real-time location updates, and geofencing.

7 min read
hard

Design a Food Delivery System

Design a food delivery system (DoorDash/Uber Eats) with three-sided marketplace, order tracking, driver dispatch, and ETA calculation.

10 min read
hard

Design Google Docs

System design interview solution for Design Google Docs. Includes requirements, API design, data model, architecture, scaling strategy, and tradeoffs.

7 min read
hard

Design Google Maps

Design Google Maps with graph routing (Dijkstra/A*), tile rendering, real-time traffic, geocoding, and turn-by-turn navigation.

8 min read
hard

Design Zoom

Design Zoom with WebRTC, SFU architecture, screen sharing, recording, and NAT traversal.

8 min read
hard

Design Dropbox

Design Dropbox with file sync, chunking, deduplication, conflict resolution, and delta sync. Covers the sync protocol and metadata management.

10 min read
hard

Design a Ticket Booking System

Design a ticket booking system (BookMyShow/Ticketmaster) with seat selection, temporary holds, concurrent booking prevention, and event management.

8 min read
hard

Design a Web Crawler

Design a distributed web crawler with URL frontier, politeness policies, content deduplication, and distributed coordination.

8 min read
hard

Design a Code Deployment System

Design a CI/CD deployment system with build pipelines, canary and blue-green deployments, automated rollback, and artifact management.

8 min read
hard

Design Cloud Storage (S3)

Design an object storage system like S3 with erasure coding, metadata service, multi-tenancy, and 11 nines of durability.

8 min read
hard

Design a Distributed Lock Service

Design a distributed lock service with consensus-based locking, fencing tokens, TTLs, and leader election. Covers Chubby/ZooKeeper architecture patterns.

8 min read