The pickLink checked Oct 9
System Design Primer
github.comFree guide to designing large-scale systems
FreeNo signup
That one website that teaches you how big websites are built to handle millions of users
Why it's the pick
A free guide to how large systems are put together: servers, databases, caching and load balancing, with worked examples like designing a link shortener. It is written for interview prep, but it reads well for anyone curious how big sites stay up.
Know a better one? Tell us Made System Design Primer? Get the badgeAlso good
System Design Primer is also the pick for helps you write code right inside your editor, gives Claude ready-made skills it can use for documents, design and more, turns a PDF, Word file or slide deck into clean Markdown for AI, checks your developer computer for compromised packages and extensions, finds a free API for almost anything, gives you a ready-made .gitignore file for your project, helps you opt out of data broker sites, walks you through building your own database, game or even Git from scratch.
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