Multi-project involvement and volunteer developers’ continued contributions to open source software projects

Open source software (OSS) ecosystems consist of projects that compete for volunteer developers who divide their attention across projects. Multi-project involvement makes it challenging for a focal project to attract a critical mass of volunteers to make long-term continued code contributions. Adopting a context-specific theorizing approach, we extend established OSS motivation literature to the multi-project context by examining how developers' continued focal project contributions are affected by the relative attractiveness of competing projects with which they are concurrently involved. Specifically, we focus on two well-established extrinsic motivators, developer status and project success, and examine how their relative values across a developer's project portfolio influence continued contribution to a focal project. Using data from 2931 volunteer developers affiliated with 445 focal projects and 4448 competing projects hosted on Google Code, we find that developers' continued contribution to a focal project is heightened when they have lower relative status in competing projects and when competing projects have lower relative success than the focal project. Asymmetrically, we also find that continued contribution to the focal project is not diminished when developers have higher relative status in competing projects or when those projects are more successful than the focal project. These findings extend work on continued contribution by highlighting the multi-project embedded nature of work performed in OSS ecosystems and have important implications for understanding developer retention across projects.