This grant provides funding to extend a project by Laura Dabbish of Carnegie Mellon University to study women’s participation in open source software projects. Combining qualitative interviews with network analysis of large-scale project data from GitHub, Dabbish broadens the definition of “participation” beyond code commits, cataloged the various ways software projects telegraph openness to new contributors, and hypothesized that gendered difference in the social network structures men and women create explain why women on average disengage from open source participation earlier than men. Grant funds will allow Dabbish to expand her work to other open source software ecosystems while also probing the gender dynamics of “maintainers,” those leaders in open source projects responsible for the technical and social “invisible work” that holds a project together. In addition, Dabbish and her partners will pilot an extension of their methods to the study of other underrepresented minorities in open source, starting with the experience of U.S.-born Black women contributors.