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scalability

17 articles across 6 sub-topics

Sub-topic

System Design

9 articles

ID Generation Strategies in System Design: Base62, UUID, Snowflake, and Beyond

TLDR: Short shareable IDs need Base62 (URL shorteners). Database primary keys at scale need time-ordered IDs (Snowflake, UUID v7). Security tokens need random IDs (UUID v4, NanoID). Picking the wrong

26 min read
Write-Time vs Read-Time Fan-Out: How Social Feeds Scale

Write-Time vs Read-Time Fan-Out: How Social Feeds Scale

TLDR: Fan-out is the act of distributing one post to many followers' feeds. Write-time fan-out (push) pre-computes feeds at post time — fast reads but catastrophic write amplification for celebrities.

18 min read

System Design HLD Example: Hotel Booking System (Airbnb)

TLDR: A robust hotel booking system must guarantee atomicity in inventory subtraction. The core trade-off is Consistency vs. Availability: we prioritize strong consistency for the booking path (Postgr

15 min read

System Design HLD Example: E-Commerce Platform (Amazon)

TLDR: A large-scale e-commerce platform separates catalog, cart, inventory, orders, and payments into independent microservices. The core architectural challenge is Inventory Correctness during flash

13 min read

System Design HLD Example: Collaborative Document Editing (Google Docs)

TLDR: Real-time collaborative editing relies on Operational Transformation (OT) or CRDTs to resolve concurrent edits without data loss. The core trade-off is Latency vs. Consistency: we use optimistic

14 min read
System Design HLD Example: URL Shortener (TinyURL and Bitly)

System Design HLD Example: URL Shortener (TinyURL and Bitly)

TLDR: A URL shortener is a read-heavy system (100:1 ratio) that maps long URLs to short, unique aliases. The core scaling challenge is generating unique IDs without database contention—solved using a

19 min read

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