Socio-Technical Dependencies in Forked OSS Projects: Evidence from the BSD Family

Existing studies show that open source projects may enjoy high level of socio-technical congruence despite their open and distributed character. Such observation is yet to be confirmed in the case of forking, where projects originating from the same root evolve in parallel and are typically lead by different development teams. In this paper, we empirically investigate the endogenous and exogenous characteristics of BSD family projects related to sociotechnical congruence. Our motivation is that BSD family, as a representative example of forked projects, share a common development ground for both the code-base and the development community, which may influence their evolution from a socio-technical perspective. Our study results show that the BSD family maintain a certain level of collaboration throughout the project history, mainly due to a shared portion of the community. This partly explains the relative harmony of socio-technical congruence levels in the BSD projects.