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In-depth, interview-ready material for backend engineers. Pick a track below and start reading — everything is open.
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11 modules
System Design Fundamentals
Core building blocks — scalability, CAP, caching, load balancing, databases, and back-of-the-envelope math.
Browse25 problems
System Design Masterclass
Interview-style problems from Netflix, Uber, Google & Stripe — with clarifying questions, trade-offs, and full solutions.
Browse15 papers
Whitepapers
Guided deep-dives into the papers that shaped distributed systems: MapReduce, Raft, Dynamo, Bigtable, and more.
Browse10 deep-dives
Real Systems
How production systems like Redis, Kafka, and Postgres actually work under the hood.
Browse24 articles
Blog
Strategies, frameworks, and guides for preparing for system design interviews.
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