Part 1 — Fundamentals

The bedrock. Every senior engineer has these concepts deeply internalized.

Prerequisites: Basic understanding of web servers and HTTP. No distributed systems experience needed.

Overview

Part 1 establishes the mental models and vocabulary you'll use throughout the entire handbook. Do not skip this section — the frameworks learned here appear in every subsequent chapter.

By the end of Part 1, you'll be able to:

Explain the key properties of distributed systems
Choose between vertical and horizontal scaling strategies
Apply the CAP theorem to real database choices
Estimate capacity requirements for any system in minutes

Chapters

Chapter 01 — Introduction to System Design

What system design is, why distributed systems exist, key properties (scalability, reliability, availability), and the 4-step interview framework.

Chapter 02 — Scalability

Vertical vs horizontal scaling, stateless architectures, scaling patterns, and how Netflix scaled from DVD rental to 300M+ subscribers.

Chapter 03 — Core Trade-offs

CAP theorem, ACID vs BASE, consistency models (strong, eventual, causal), availability patterns, and real-world trade-off examples.

Chapter 04 — Back-of-Envelope Estimation

Powers of 2, latency numbers, QPS/storage/bandwidth estimation techniques, and worked examples for Twitter and YouTube.

Time Estimate

~4 hours of focused reading and practice.