System Design
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1 docsTier 1 -- Building Blocks
26 docsScale Reads
Scale Writes
Sharding & Partitioning (Hash-based, Range-based, Geo-based)9 min read · sharding-partitioning
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Database Selection
SQL Databases (PostgreSQL, MySQL) — ACID, Joins, Strong Consistency9 min read · sql-databases
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Wide-Column Store (Cassandra, HBase) — AP, Massive Write Throughput10 min read · wide-column-store
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Traffic Control
Consistency & Coordination
Tier 2 -- Core Systems
11 docsNotification System — System Design Interview14 min read · notification-system
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Search Autocomplete System — System Design Interview13 min read · search-autocomplete-system
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Web Crawler — System Design Interview12 min read · web-crawler
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Twitter (Timeline + Trending Topics) — System Design Interview17 min read · twitter
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Instagram (Photo Sharing) — System Design Interview18 min read · instagram
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Google Drive (Cloud Storage) — System Design Interview18 min read · google-drive
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YouTube (Video Streaming) — System Design Interview18 min read · youtube
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Tier 3 -- Location & Real-Time
4 docsProximity Service (Yelp) — System Design Interview15 min read · proximity-service
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Nearby Friends — System Design Interview15 min read · nearby-friends
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Uber / Ride-Hailing Service — System Design Interview17 min read · uber
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Google Maps — System Design Interview17 min read · google-maps
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Tier 4 -- Infrastructure & Data
7 docsDistributed Cache (Memcached)12 min read · distributed-cache
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Content Delivery Network (CDN)10 min read · cdn
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Distributed Message Queue — System Design Interview13 min read · distributed-message-queue
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S3-like Object Storage10 min read · s3-object-storage
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Metrics Monitoring and Alerting System10 min read · metrics-monitoring-alerting
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Top K / Heavy Hitters Problem10 min read · top-k-heavy-hitters
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Ad Click Event Aggregation9 min read · ad-click-event-aggregation
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Tier 5 -- Finance & Commerce
8 docsReal-Time Gaming Leaderboard9 min read · gaming-leaderboard
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Hotel Reservation System7 min read · hotel-reservation-system
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Ticketmaster (Event Booking)10 min read · ticketmaster
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E-Commerce Platform (Amazon)9 min read · ecommerce-platform
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Digital Wallet9 min read · digital-wallet
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Payment System8 min read · payment-system
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Distributed Email Service9 min read · distributed-email-service
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Stock Exchange10 min read · stock-exchange
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Tier 6 -- Advanced & Collaborative
6 docsNews Aggregator (Google News)10 min read · news-aggregator
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Social Graph / Social Network10 min read · social-graph
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Recommendation System9 min read · recommendation-system
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Dropbox (File Sync Service)9 min read · dropbox
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Google Docs (Real-Time Collaboration)9 min read · google-docs
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Twitch (Live Streaming)9 min read · twitch
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