Who? Where? What? Examining distributed development in two large open source projects

To date, a large body of knowledge has been built up around understanding open source software development. However, there is limited research on examining levels of geographic and organizational distribution within open source software projects, despite many studies examining these same aspects in commercial contexts. We set out to fill this gap in OSS knowledge by manually collecting data for two large, mature, successful projects in an effort to assess how distributed they are, both geographically and organizationally. Both Firefox and Eclipse have been the subject of many studies and are ubiquitous in the areas of software development and internet usage respectively. We identified the top contributors that made 95% of the changes over multiple major releases of Firefox and Eclipse and determined their geographic locations and organizational affiliations. We examine the distribution in each project´s constituent subsystems and report the relationship of pre- and post-release defects with distribution levels.