From the Cathedral to the Bazaar: An Empirical Study of the Lifecycle of Volunteer Community Projects

Some free software and open source projects have been extremely successful in the past. The success of a project is often related to the number of developers it can attract: a larger community of developers (the `bazaar') identifies and corrects more software defects and adds more features via a peer-review process. In this paper two free software projects (Wine and Arla) are empirically explored in order to characterize their software lifecycle, development processes and communities. Both the projects show a phase where the number of active developers and the actual work performed on the system is constant, or does not grow: we argued that this phase corresponds to the one termed 'cathedral' in the literature. One of the two projects (Wine) shows also a second phase: a sudden growing amount of developers corresponds to a similar growing output produced: we termed this as the `bazaar' phase, and we also argued that this phase was not achieved for the other system. A further analysis revealed that the transition between `cathedral' and `bazaar' was a phase by itself in Wine, achieved by creating a growing amount of new modules, which attracted new developers.