Cloud-Native Evolution

Chapter 3. Beginning of Microservices

Although a lift-and-shift approach to migrating a monolithic application allows for quick migration and can save on short-term costs, the operational costs of running software that has not been optimized for the cloud will eventually overtake the cost of development. The next stage toward cloud-native is adopting a microservice architecture to take advantage of improved agility and scalability.

Embrace a Microservices Architecture

In a microservices architecture, applications are composed of small, independent services. The services are loosely coupled, communicating via an API rather than via direct method calls, as in tightly coupled monolithic application. A microservices architecture is more flexible than a monolithic application, because it allows you to independently scale, update, or even completely replace each part of the application.

It can be challenging to determine where to begin when migrating from a large legacy application toward microservices. Migrate gradually, by splitting off small parts of the monolith into separate services, rather than trying to reimplement everything all at once. The first candidates for splitting off into microservices are likely to be those parts of the application with issues that need to be addressed, such as performance or reliability issues, because it makes sense to begin by redeveloping the parts of the application that will benefit most from being migrated to the cloud.

Another challenge with ...