Mining Experts from Source Code Analysis: An Empirical Evaluation

Abstract

Modern software development increasingly depends on third-­party libraries to boost productivity and quality. This development is complex and requires specialists with knowledge in several technologies, such as the nowadays libraries. Such complexity turns it extremely challenging to deliver quality software, given the pressure. For this purpose, it is necessary to identify and hire qualified developers, to obtain a good team, both in open source and proprietary systems. For these reasons, enterprise and open source projects try to build teams composed of highly skilled developers in specific libraries. However, their identification may not be trivial. Despite this fact, we still lack procedures to assess developers skills in widely popular libraries. In this paper, we first argue that source code activities can identify software developers’ hard skills, such as library expertise. We then evaluate a mining­-based strategy to reduce the search space to identify library experts. To achieve our goal, we selected the 9 most popular Java libraries and 6 libraries for microservices (i.e., 15 libraries in total). We assessed the skills of more than 1.5 million developers in these libraries by analyzing their commits in more than 17 K Java projects on GitHub. We evaluated the results by applying two surveys with 158 developers. First, with 137 library expert candidates, they observed 63% precision for popular Java libraries’ used strategy. Second, we observe a precision of at least 71% for 21 library experts in microservices. These low precision values suggest space for further improvements in the evaluated strategy.