  Tools and artifacts produced by open source software (OSS) have been woven
into the foundation of the technology industry. To keep this foundation intact,
the open source community needs to actively invest in sustainable approaches to
bring in new contributors and nurture existing ones. We take a first step at
this by collaboratively designing a maintainer dashboard that provides
recommendations on how to attract and retain open source contributors. For
example, by highlighting project goals (e.g., a social good cause) to attract
diverse contributors and mechanisms to acknowledge (e.g., a "rising
contributor" badge) existing contributors. Next, we conduct a project-specific
evaluation with maintainers to better understand use cases in which this tool
will be most helpful at supporting their plans for growth. From analyzing
feedback, we find recommendations to be useful at signaling projects as
welcoming and providing gentle nudges for maintainers to proactively recognize
emerging contributors. However, there are complexities to consider when
designing recommendations such as the project current development state (e.g.,
deadlines, milestones, refactoring) and governance model. Finally, we distill
our findings to share what the future of recommendations in open source looks
like and how to make these recommendations most meaningful over time.

Software Engineering;Computers and Society;Human-Computer Interaction