The processes of joining in global distributed software projects

Libre (free / open source) software is a good example of global software development. Thousands of projects, in a wide range of domains which involve hundreds of thousands of developers and contributors from all around the world. Some large (both in size and developer community) libre software projects have shown evidence of producing code with complete functionality and fast evolution (with linear or superlinear growth), while maintaining low defect density. Many companies are exploring how to benefit from this situation, considering several approaches related to libre software development. For instance, some of them have hired full-time developers, focusing their work on some libre software projects they consider strategic.However, before joining the core development team of the project, these hired developers have to follow a process of software comprehension, and get used to the rules and communication mechanisms used in the project. We were interested in the differences between this case and that of volunteer developers working in the same project, Therefore, we studied the duration and basic characteristics of this joining process for the developers of GNOME (a well known, large, libre software project). In our analysis, we have found two groups with clearly different joining patterns. Moreover, we have related those patterns to the different behaviors of volunteer and hired developers: volunteers tend to follow a step-by-step joining process, while hired developers usually experiencea "sudden" integration. Some reasons for this different behavior are also discussed.