Software Architect's Handbook

Transforming monoliths to microservices

Your legacy application may have a monolithic architecture. In Chapter 8, Architecting Modern Applications, we learned that a monolithic application is designed to work as a single, self-contained unit. The code may have components that are tightly coupled and highly interdependent. If the application is large and complicated, it can be difficult to make changes to a monolithic application.

One approach to modernizing a legacy application is to begin introducing microservices. Microservices are small, focused, autonomous services that are independently deployable. Unlike a monolithic application, the microservice approach reduces the level of complexity by partitioning an application into small services ...