Code, quality, and process metrics in graduated and retired ASFI projects.

Recent work on open source sustainability shows that successful trajectories of projects in the Apache Software Foundation Incubator (ASFI) can be predicted early on, using a set of socio-technical measures. Because OSS projects are socio-technical systems centered around code artifacts, we hypothesize that sustainable projects may exhibit different code and process patterns than unsustainable ones, and that those patterns can grow more apparent as projects evolve over time. Here we studied the code and coding processes of over 200 ASFI projects, and found that ASFI graduated projects have different patterns of code quality and complexity than retired ones. Likewise for the coding processes – e.g., feature commits or bug-fixing commits are correlated with project graduation success. We find that minor contributors and major contributors (who contribute <5%, respectively >=95% commits) associate with graduation outcomes, implying that having also developers who contribute fewer commits are important for a project’s success. This study provides evidence that OSS projects, especially nascent ones, can benefit from introspection and instrumentation using multidimensional modeling of the whole system, including code, processes, and code quality measures, and how they are interconnected over time.