About microservices.io

Microservices.io is brought to you by Chris Richardson. Experienced software architect, author of POJOs in Action and the creator of the original CloudFoundry.com. His latest startup is eventuate.io, a microservices application platform.

Learn more about microservices

Chris offers a comprehensive set of resources for learning about microservices including articles, an O'Reilly training video, and example code. Learn more

Microservices consulting and training

Chris offers a comprehensive consulting services, workshops and hands on training classes to help you use microservices effectively. Get advice

Need training in London?

I'll be there in May! Contact me

Example microservices applications

Want to see an example? Check out Chris Richardson's example applications. See code

The patterns

How to apply the patterns

Core patterns


Deployment patterns

Cross cutting concerns

Communication style

External API

Service discovery


Data management




UI patterns

Signup for the newsletter

A new microservices application platform that solves distributed data management problems.

Join the microservices google group

Pattern: Decompose by subdomain


You are developing a large, complex application and want to use the microservice architecture.


How to decompose an application into services?


  • The architecture must be stable
  • Services must be cohesive and loosely coupled
  • Each team that owns one or more services must be autonomous


Define services corresponding to Domain-Driven Design (DDD) subdomains. DDD refers to the application’s problem space - the business - as the domain. A domain is consists of multiple subdomains. Each subdomain corresponds to a different part of the business.


The subdomains of an online store include:

  • Product catalog
  • Inventory management
  • Order management
  • Logistics

The corresponding microservice architecture would have services corresponding to each of these subdomains.

Resulting Context

This pattern has the following benefits:

  • Stable architecture since the subdomains are relatively stable
  • Development teams are cross-functional, autonomous, and organized around delivering business value rather than technical features
  • Services are cohesive and loosely coupled


There are the following issues to address:

  • How to identify the subdomains? Identifying subdomains and hence services requires an understanding of the business. Subdomains are identified by analyzing the business and it’s organizational structure and identifying the different areas of expertise.

Copyright © 2017 Chris Richardson • All rights reserved • Supported by Kong.