Network Analysis of Software Repositories: Identifying Subject Matter Experts

A software developer joining a large software project faces a steep learning curve before they are able to make real contributions. One challenge is finding the subject matter experts who can answer questions about a specific area of the software or to review changes. This is especially true of large projects with many modules and a large number of authors. In this paper, we describe a method to model a software project as a network using information mined from the project’s version control repository, and demonstrate how network analysis techniques can be used to identify the key authors and subject matter experts. We investigate metrics that can be gathered using network analysis, such as which groups of authors typically work together, and how closely knit the developers are on a project. We analyze several specific projects to demonstrate the applicability of these techniques and several hundred projects to show general trends.