Creator here. I made this after looking for an open source project to start contributing to in order to improve my skills. While GitHub lets you find new projects by language or stars, it doesn't make it easy to find projects according to other important factors like whether my first pull request is likely to be accepted or even looked at and whether it's more for full-time contributors or evenings and weekenders.

So I made SourceSort to make this easier. Most of the data comes from extra analysis on top of the GitHub API, and some of it's manual labor. There are a few hundred projects on there now and I'll be adding some more soon.

Let me know if you have any questions and I'd love to hear more ideas on what other metrics I should add.