This is self-hosted but I’m pretty sure it’s not Open Source (or even available source) like Baserow

I never see a mention of this even at any of the "awesome" lists but this is really well built and has more features than baserow.

Baserow's mobile support is quite poor but Seatable does it very well and I've been using it for several months and love it.

Seatable doesn't appear to be open source, and for some reason the website is incredibly janky on Firefox

Server component seems proprietary but you can easily run it via docker.

https://github.com/seatable/seatable#license