An open source framework for understanding system design. Used at UC Berkeley.
AI can write code faster than any human. But it cannot decide what to build. The engineers who thrive in the AI era are the ones who understand the architectural patterns behind every system. This framework gives you that understanding.
AI tools generate implementation. You provide the architecture. Knowing which building blocks to compose and why is the skill that matters most.
Instagram, Netflix, Uber, Slack, Stripe. Different products, same 7 building blocks. Learn the pattern once, apply it to any system.
The framework is free. Read the articles, try the challenges, use it in your work and interviews. No account required.
Every software system is composed from these 7 universal building blocks. Two handle tasks, five handle storage. Together they can model any system.
Receives a request, does work, sends a response. The backbone of every API.
Picks up tasks from a queue and processes them in the background, at its own pace.
Lightning-fast lookups by key. Caching, sessions, feature flags.
Stores large blobs: images, videos, PDFs. Optimized for size, not queries.
Decouples producers from consumers. Makes systems resilient to spikes and failures.
Structured data with relationships. Transactions, constraints, complex queries.
Similarity search for AI. Find content by meaning, not exact match.
Seven articles that take you from zero to fluent in the building blocks framework. Read them in order, or jump to what interests you.
Design Instagram, Netflix, and Uber using building blocks. Each challenge gives you requirements and asks you to pick the right blocks and compose them into a working system.
Try the ChallengesRead additional articles on system design, software architecture, and thinking in systems.
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