Understanding software evolution: the maisqual ant data set

Software engineering is a maturing discipline which has seen many drastic advances in the last years. However, some studies still point to the lack of rigorous and mathematically grounded methods to raise the field to a new emerging science, with proper and reproducible foundations to build upon. Indeed, mathematicians and statisticians do not necessarily have software engineering knowledge, while software engineers and practitioners do not necessarily have a mathematical background. The Maisqual research project intends to fill the gap between both fields by proposing a controlled and peer-reviewed data set series ready to use and study. These data sets feature metrics from different repositories, from source code to mail activity and configuration management meta data. Metrics are described and commented, and all the steps followed for their extraction and treatment are described with contextual information about the data and its meaning. This article introduces the Apache Ant weekly data set, featuring 636 extracts of the project over 12 years at different levels of artefacts – application, files, functions. By associating community and process related information to code extracts, this data set unveils interesting perspectives on the evolution of one of the great success stories of open source.