  Open-source developers, particularly the elite developers, maintain a diverse
portfolio of contributing activities. They do not only commit source code but
also spend a significant amount of effort on other communicative,
organizational, and supportive activities. However, almost all prior research
focuses on a limited number of specific activities and fails to analyze elite
developers' activities in a comprehensive way. To bridge this gap, we conduct
an empirical study with fine-grained event data from 20 large open-source
projects hosted on GitHub. Thus, we investigate elite developers' contributing
activities and their impacts on project outcomes. Our analyses reveal three key
findings: (1) they participate in a variety of activities while technical
contributions (e.g., coding) accounting for a small proportion only; (2) they
tend to put more effort into supportive and communicative activities and less
effort into coding as the project grows; (3) their participation in
non-technical activities is negatively associated with the project's outcomes
in term of productivity and software quality. These results provide a panoramic
view of elite developers' activities and can inform an individual's decision
making about effort allocation, thus leading to finer project outcomes. The
results also provide implications for supporting these elite developers.
