%0 Journal Article %J ACM Transactions on Software Engineering and Methodology %D 2002 %T Two case studies of open source software development: Apache and Mozilla %A Audris Mockus %A Roy Fielding %A Herbsleb, J. D. %K apache %K bug fixing %K bug reports %K bugzilla %K change history %K core %K defect density %K email %K email archives %K mailing list %K mozilla %K ownership %K participation %K productivity %K scm %K source code %X According to its proponents, open source style software development has the capacity to compete successfully, and perhaps in many cases displace, traditional commercial development methods. In order to begin investigating such claims, we examine data from two major open source projects, the Apache web server and the Mozilla browser. By using email archives of source code change history and problem reports we quantify aspects of developer participation, core team size, code ownership, productivity, defect density, and problem resolution intervals for these OSS projects. We develop several hypotheses by comparing the Apache project with several commercial projects. We then test and refine several of these hypotheses, based on an analysis of Mozilla data. We conclude with thoughts about the prospects for high- performance commercial/ open source process hybrids. %B ACM Transactions on Software Engineering and Methodology %V 11 %P 309-346 %G eng %M WOS:000177759000002 %1 software engineering %2 case study %> https://flosshub.org/sites/flosshub.org/files/mockusFieldingHerbsleb2002.pdf %0 Journal Article %J Proceedings of the International Conference on Software Engineering (ICSE 2000) %D 2000 %T A Case Study of Open Source Software Development: The Apache Server %A Audris Mockus %A Roy Fielding %A Herbsleb, James %K apache %K bug fix revisions %K bugs %K core %K cvs %K defect density %K developers %K email archives %K participation %K productivity %K revision control %K revision history %K roles %K scm %K source code %K team size %X According to its proponents, open source style software development has the capacity to compete successfully, and perhaps in many cases displace, traditional commercial development methods. We examine the development process of a major open source application, the Apache web server. By using email archives of source code change history and problem reports we quantify aspects of developer participation, core team size, code ownership, productivity, defect density, and problem resolution interval for this OSS project. This analysis reveals a unique process, which performs well on important measures. %B Proceedings of the International Conference on Software Engineering (ICSE 2000) %8 June %G eng %> https://flosshub.org/sites/flosshub.org/files/mockusapache.pdf