News (November 2022): Our patterns form the core of the book “Patterns for API Design: Simplifying Integration with Loosely Coupled Message Exchanges” in the Vaughn Vernon Signature series at Addison-Wesley Professional.

The MAP for Open API Design and Evolution

While much has been said about microservices in general and about supporting infrastructure architectures, the service API design has received less attention:

• How many services should be exposed remotely? What is an adequate size for them?
• How to ensure that the services provided by an API and their interactions with clients are loosely coupled? How much data should be exchanged in request and response messages? How often does this happen?
• What are the most suitable message representations? How to agree on the meaning of each message?

Answering these questions is what this website is about. Our API design pattern language is organized into categories:

Eager to get going? Looking for more context and background information?

• This presentation and the cheat sheet are good places to get started with MAP. Several tutorials are available. The resources page suggests more entry points.
• Selected patterns are implemented in the Lakeside Mutual sample application (see here). Lakeside Mutual is a fictitious insurance company that implemented its core business capabilities for customer, contract, and risk management as a set of microservices with corresponding application frontends.
• Microservice Domain Specific Language (MDSL) features all patterns in combination.
• The Stepwise Service Design activity proposed in the Software/Service/API Design Practice Repository (DPR) leverages many of the our patterns.¹
• (since 2021) An API refactoring catalog is emerging.

Guidance and Pointers

You can continue reading about MAP and related topics on any of these pages:

Feedback and input is appreciated! Contact us.