System Internals

Developer-focused guides to how widely-used systems work under the hood — architecture, core algorithms, and data flow, with light-theme block diagrams. Plus interview prep playbooks.

System Internals Guides

Interview Playbooks

System Design Interview · Foundations

System Design Interview · Counting & Analytics

System Design Interview · Feeds, Messaging & Social

System Design Interview · Search, Geo & Logistics

System Design Interview · Media & Collaboration

System Design Interview · Coordination, Money & Markets

System Design Interview · Patterns

Leadership Interview Prep