There is a whole page about this https://herdr.dev/compare/

For me the killer feature is the git worktree management.

But in essence it is tmux on steroid (Specifically for agents)

I wonder if it works with jj workspaces as well. I guess I have something new to tryout today

Sadly it does not. There are both a discussion about support for non-git vcs (https://github.com/ogulcancelik/herdr/discussions/522) and about jj specifically.

Hopefully any of those get some traction

I did find a plugin at least