[mkayokay]

How are commands handled, that require user input? E.g. password for sudo in your example:

  sshsync group web-servers "sudo systemctl restart nginx"

I like that you included a demo in the README, but it is too long for a gif, as I can't pause/rewind/forward. So splitting into multiple short gifs or converting into a video (if GitHub supports them) could improve the experience.

[blackmamoth]

As of now there is no way to take user input in transit, so either the user is required to have the privilege to execute the specified command or have passwordless sudo available.

And Yeah, now that you've mentioned it multiple shorter gifs would be better.

[mrbluecoat]

Or https://asciinema.org/ instead of gifs