A circular dependency is a relationship between two or more application modules that are codependent on each other. Circular dependencies in a microservices-based application can impact the ability of services to scale or independently deploy. 

Circular dependencies also make code difficult to read and maintain over time. If circular dependencies multiply, any changes to a single module will likely cause errors for others. It’s also extremely difficult to reuse tightly-coupled modules since their code carries all their dependencies. 

How to reduce circular dependencies? 

Reordering dependencies – To reduce circular dependencies, architects can implement loose component coupling and isolate failures. One such approach is to use abstraction to break the dependency chain. 

Adopt the Dependency Structure Matrix – DSM is a simple and compact way of mapping the dependencies that exist among the components of an application. The visual representation of the architecture’s coupling can help software teams navigate testing and quickly detect bugs.

Use tools to fix dependencies – The right tooling is extremely helpful when it comes to addressing circular dependencies among microservices. Lattix architect, Stan4J, Structure101 are some of the tools designed to manage dependencies in microservices applications. 

Read on to know more about circular dependencies and how to reduce or eliminate them.