Thinking in Systems
The Mental Model
Explain Like I'm 5
What is Systems Design?
Systems Design is like being an architect for software. Before you build a house, you decide where the rooms go, how water flows through pipes, and where the electrical wires run. For software, you design how data flows, where things are stored, and how millions of users can use it at once.
Think of it like this...
Imagine designing a restaurant. You need to think about: How many customers can fit? Where does the kitchen go? How do orders flow from tables to chefs? That's systems design—but for apps that serve millions!
Key Concepts
🔄The Request Journey
The First Principle
Every systems design problem comes back to one question: How do we handle MORE? More users, more data, more requests. Design for growth, not for today.
Core Design Concepts
These building blocks solve 90% of scaling problems
Twitter — Systems thinking in social media
Twitter processes 500M+ tweets/day. Every tweet must be delivered to millions of followers in real-time. This requires caching (fanout on read vs write), message queues, and distributed databases working in concert.
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