Dealing with Dependency: How Dependencies Shape Release Frequency in the Maven Ecosystem

Reuse of external libraries and components is a common practice in modern software development. However, the dependencies created from such reuse have implications on bugpropagation, deprecation, and releases scheduling. This paper presents a large empirical study on dependencies and their impacts on release frequencies of libraries/artifacts having different levels of dependencies. Through an in-depth quantitative analysis of a public dataset representing the Maven Central Repository, we have found that there exists globally central libraries, which millions of other artifacts depend on. There also exists local community clusters of artifacts having much dependencies on each other, and some libraries/artifacts are found shared across community clusters forming bridges between. Surprisingly, it was found that the most frequent releases are experienced by the libraries having zero or very few dependencies and also those libraries having the most dependencies, while the libraries in the middle undergo moderately frequent releases. The results of this study emphasizes that especial care should be given to the maintenance of central and bridge artifacts/libraries because the overall stability and health of the entire Maven ecosystem are critically dependent on them.