Extending Supabase with your own back end

I'm very invested in Supabase. When I saw the title I thought this was going to be about extending self-hosted Supabase in a similar way as you can do in PocketBase[1] with go.

Still, interesting to read about how others use it.

[1]: https://pocketbase.io

This is essentially just copy/paste from Supabase documentation with light commentary. Am I missing something?