The Open Source Index
The Most Popular & Fastest Growing Open-Source Projects on GitHub
Two Sigma Ventures
The Open Source Index
Welcome to the Two Sigma Ventures Open Source Index, our directory of the top 100 most popular and fast-growing open-source projects on GitHub. We hope the data we publish here, which will be updated regularly, will be valuable for entrepreneurs, developers, investors, and anyone interested in following the growth of open source software. If you have any suggestions on how we can improve, please don’t hesitate to reach out.
We started by using the GitHub API to download all publicly available data on the top GitHub projects ranked by number of “Watchers.” Most other lists that rank open source projects use Stars as their “north star” metric, no pun intended. However, we believe that over time, GitHub Stars has become a vanity metric that is often gamed and that Watchers is instead a more telling signal of ongoing interest in a project. When a user elects to “Watch” a project on GitHub, they receive notifications about the project and its relevant discussions. When users are no longer interested in a project, they often will un-Watch that repository. Therefore, we believe that Watchers are a more interesting signal of sustained project popularity than Stars. Additionally, using license information and through manual sorting, we filtered out non-technical projects, such as books, lists, and educational content.
Our Index ranks projects using what we call the “TSV Score.” The score is a weighted average of the variables listed below, which we normalized to fit our scale of 0 to 100. The weights we chose are listed in parentheses.
- Watchers (40%) – our main metric we use to assess project popularity, as described above, is the number of Watchers per project.
- Watcher growth (25%) – we computed the delta in watchers over the past quarter and believe it gives us an important signal on which projects have momentum in the developer ecosystem.
- Contributors (15%) – the number of contributors provides us a sense of the developer community and interest for a given project.
- Release cadence (10%) – we compute release cadence as the number of commits a project has had over its lifetime. While this can be influenced heavily by individual contributors’ commit patterns and doesn’t give us a sense of more recent contributions, we still believe this metric provides us an indication of the pace at which a project evolves and grows.
- Community health score (10%) – finally, we take into account GitHub’s own Community Health Score metric, which evaluates how well-maintained a repository and its docs are.
We understand that these weights are arbitrary and reflect just one perspective on what’s important in building a great open source community. We’d love to share the raw data with you and have you play around with various weights and other data sources. Let us know if you’d like a copy!