Article 02: Designing Microservices the Right Way

1. Objective

Learn how to identify correct service boundaries and avoid poor microservice design.

2. Key Concepts

• Domain-Driven Design (DDD)
• Bounded Context
• Service ownership
• High cohesion, low coupling

3. Real-World Analogy

A company structure:

• HR, Finance, Engineering work independently
• Each has clear responsibilities

4. Bounded Context Explained

A bounded context defines where a particular model applies consistently.

Example:

• User Context
• Order Context
• Payment Context

5. Hands-On: Design Exercise

Design a Food Ordering System:

• User Service: Authentication, profile
• Order Service: Orders, status
• Payment Service: Transactions

6. Simple Diagram

[User Service] ---> [Order Service] ---> [Payment Service]

7. Common Mistakes

• Sharing databases
• Chatty inter-service communication
• God services

8. Interview Notes

• DDD helps prevent tight coupling.
• Good boundaries reduce future refactoring.

9. Summary

Design matters more than implementation in microservices.

10. What’s Next

Start building your first microservice with Spring Boot.