Evaluating Microservice Organizational Coupling Based on Cross-Service Contribution

For traditional modular software systems, “high cohesion, low coupling” is a recommended setting while it remains so for microservice architectures. However, coupling phenomena commonly exist therein which are caused by cross-service calls and dependencies. In addition, it is noticeable that teams for microservice projects can also suffer from high coupling issues in terms of their cross-service contribution, which can inevitably result in technical debt and high managerial costs. Such organizational coupling needs to be detected and mitigated in time to prevent future losses. Therefore, this paper proposes an automatable approach to evaluate the organizational coupling by investigating the microservice ownership and cross-service contribution. Furthermore, we validate the feasibility of the approach using a case study of a popular microservice project. The results show that, with sufficient software repository data, we can not only evaluate the organizational coupling in microservice system projects but also continuously monitor its evolution.