Clubs are projects with high contributor growth and low user growth, leading to a roughly overlapping group of contributors and users. While there are fewer users overall, these users are more likely to participate as contributors. Astropy, for example, is a package that provides core functionality and tooling for those using Python for astronomy and astrophysics. While Astropy will never be used by most developers, the package’s narrow focus makes it easier to recruit contributors and maintain relevance among those for whom Astropy is extremely important.
