Prerequisites & Learning Path

System Design is a vast field. Without a structured approach, learners often bounce randomly between topics—reading about microservices before understanding distributed systems fundamentals, or studying specific technologies (Kafka, Cassandra, Redis) without grasping the underlying principles that make them appropriate for certain use cases.

This curriculum is designed with intentional structure. Every chapter builds on previous knowledge. Every module progresses from foundational concepts to advanced applications. Understanding this structure helps you learn more effectively, identify dependencies, and navigate the material strategically.

This curriculum is organized into three major parts, each serving a distinct purpose in your learning journey. Think of these as three ascending phases of mastery:

Part I: Foundations establishes the conceptual groundwork. You cannot design systems at scale without understanding what system design is, how distributed systems behave, and what fundamental challenges exist. This part answers: What is System Design, and what makes it hard?

Part II: Scalability & Performance dives into the practical patterns and technologies used to build systems that handle massive load. This part answers: How do we make systems fast, reliable, and capable of serving millions of users?

Part III: Advanced Topics & Synthesis brings everything together with real-world case studies, microservices architectures, cloud-native patterns, and interview preparation. This part answers: How do we apply everything we've learned to solve real problems?

The Foundations part comprises five carefully sequenced chapters, each establishing essential concepts that later chapters depend upon.

Chapter 1: Introduction to System Design

This opening chapter answers the fundamental question: What is System Design? It establishes system design as architectural decision-making, distinguishes it from low-level design, explains why it matters for building at scale, and prepares you for both real-world work and interviews.

Chapter 2: System Design Thinking

Before diving into technologies, you need a methodology. This chapter teaches the systematic approach: gathering requirements, performing estimation, analyzing trade-offs, identifying constraints, iterating on designs, and communicating effectively. These skills apply to every design problem.

Why This Sequence?

The progression is intentional:

1. Introduction establishes what we're learning and why
2. Thinking provides the methodology for approaching problems
3. Client-Server introduces the basic building blocks of distributed architectures
4. Distributed Fundamentals reveals the inherent challenges that make distributed systems hard
5. Coordination & Consensus shows how systems overcome these challenges

By the end of Part I, you'll have a mental model of how distributed systems work, what makes them difficult, and what tools exist to manage complexity.

With foundational understanding in place, Part II dives into the practical patterns, technologies, and strategies used to build systems that handle real-world scale. This is where theory meets implementation.

The Scalability Journey

Chapters in Part II follow the journey a system takes as it scales from handling hundreds of users to millions:

Database and Data Management

Data is often the most challenging aspect of scaling. Multiple chapters address different data concerns:

Asynchronous Processing and Communication

Not everything can be synchronous request/response. Later chapters cover:

• Chapter 14: Asynchronous Processing — Message queues, pub/sub, event-driven architecture, Kafka, RabbitMQ, SQS
• Chapter 15: API Design & Protocol — RESTful best practices, GraphQL, gRPC, WebSockets, API versioning and evolution

Part III brings together everything learned in Parts I and II, adding advanced topics and focusing on practical application. This is where you move from understanding components to architecting complete systems.

Security and Reliability

Modern Architectures

With traditional patterns understood, we explore modern architectural approaches:

Real-World Application

The curriculum culminates with practical application:

• Chapter 22: Real-World Case Studies — Deep dives into architectures of systems like Twitter, Netflix, WhatsApp, Uber, etc.
• Chapter 23: System Design Interview Mastery — Interview framework, common problems, communication strategies, time management, common pitfalls

Each chapter is divided into modules, and each module focuses on a specific concept or skill. Understanding module structure helps you navigate efficiently.

Module Components

Every module contains:

Progression Within Chapters

Modules within a chapter follow a consistent progression:

1. Conceptual Introduction — What is this thing? Why does it exist?
2. Deep Dive — How does it work? What are the details?
3. Variations and Options — What alternatives exist? When to use each?
4. Implementation Considerations — What do you need to know to use this in practice?
5. Integration — How does this work with other components?

This pattern repeats across the curriculum, creating predictable structure that aids learning.

While the curriculum is designed for sequential progression, different goals may warrant different approaches. Here are recommended learning paths based on your objectives:

Path 1: Complete Mastery (Recommended)

Follow the curriculum sequentially from Chapter 1 through Chapter 23. This path provides the most comprehensive understanding and builds knowledge systematically. Ideal for those with time to invest in deep learning.

Timeline: 3-6 months with consistent study

Path 2: Interview Preparation Focus

If preparing for interviews with limited time, prioritize:

1. Chapter 1 & 2 (Introduction and Thinking) — Essential methodology
2. Chapter 4 (Distributed Systems Fundamentals) — Core concepts for any design
3. Chapter 6-8 (Scalability, Load Balancing, Caching) — Most common design patterns
4. Chapter 10-11 (Database Fundamentals & Scaling) — Data is central to most designs
5. Chapter 22-23 (Case Studies & Interview Mastery) — Direct interview preparation

Timeline: 4-8 weeks intensive

Path 3: Backend Engineer Deepening

For working backend engineers wanting to deepen architectural skills without interview pressure:

• Complete Part I thoroughly (Chapters 1-5)
• Focus on chapters relevant to current projects
• Use case studies to learn from industry solutions
• Return to fill gaps as needed

Timeline: Ongoing, project-driven

Path 4: Specific Topic Deep Dive

If you need to understand a specific area (e.g., database scaling for a current project):

• Ensure prerequisite chapters are complete
• Study the target chapter thoroughly
• Cross-reference related chapters as needed

Certain themes recur throughout the curriculum. Recognizing these themes helps you see connections between seemingly disparate topics and develop integrated understanding.

Theme 1: Trade-offs Are Everywhere

Every design choice involves trade-offs. Consistency vs availability. Latency vs throughput. Simplicity vs flexibility. Cost vs performance. The curriculum constantly reinforces trade-off thinking because it's the core skill of system design.

Theme 2: There Is No Perfect Solution

No architecture is universally 'best.' The right design depends on requirements, constraints, team capabilities, and organizational context. The curriculum teaches you to evaluate options, not memorize 'correct' answers.

Theme 3: Scale Changes Everything

Solutions that work at small scale often fail at large scale. The curriculum repeatedly examines what happens as systems grow—from hundreds to thousands to millions of users. Developing scale intuition is a primary learning goal.

We've mapped the structure of this comprehensive System Design curriculum. Here are the key takeaways:

What's next:

With the curriculum structure understood, the next page focuses on the recommended practice approach. Learning System Design requires active practice, not passive reading. We'll explore how to approach practice effectively, what types of practice yield the best results, and how to maximize retention.