Clean Architecture in Node.js
📌 Covered in this chapter:
Layered Architecture · Dependency Injection · Separation of Concerns · Testing Boundaries
Structure a Node.js backend using clean, layered architecture — separating routes, controllers, services, repositories, and models.
1Clean Architecture in Node.js — What You'll Learn
Structure a Node.js backend using clean, layered architecture — separating routes, controllers, services, repositories, and models.
Here's everything this chapter covers, in the order you'll learn it:
- Layered architecture overview
- Routes layer
- Controllers layer
- Services layer (business logic)
- Repositories layer (data access)
- Models
- Middleware placement
- DTOs between layers
- Centralized validation
- Configuration management
- Dependency injection basics
- Centralized error handling
- Structured logging
- Defining clear testing boundaries between layers
2Best Practices & Common Pitfalls
💡 Key things to remember:
- Each layer should only know about the layer directly below it — controllers call services, services call repositories, and repositories talk to the database. This makes each layer independently testable.
❓ Frequently Asked Questions (FAQ)
Q What's the most important thing to understand about clean architecture in node.js?
Focus on: Layered Architecture · Dependency Injection · Separation of Concerns · Testing Boundaries. These are the core building blocks this chapter's examples are built around, and they show up repeatedly in later chapters of this course.
Q Do I need external npm packages for clean architecture in node.js?
Only where explicitly shown in the code examples above (like Express, Zod, or Socket.IO) — otherwise, this chapter relies entirely on Node.js's own built-in capabilities.