Don't forget projects like PyTorch, Presto, etc.
zstd is fantastic, though I suppose it's not the sort of thing that particularly needs ongoing active maintenance.
You would think that, but then you look at its release notes.
Oh, right! I forgot PyTorch was originally Facebook (and it's not under their umbrella anymore).
We still work on it tho :)
I have my doubts as to whether they can be a good citizen of the open-source community and respect the developers relying on their tools. I routinely see bugs marked “won’t fix” and nonsensical new features in the React Native ecosystem.
React[0]: JavaScript front-end web framework from Facebook. For good or ill, the most widely-used web framework in the world.
Not to say that Facebook will maintain Sapling, but React does stand as proof that they're not incapable of carrying an open source project to the finish line.
[0] https://github.com/facebook/react