#tmuxinator isn't in #ArchLinux's repos, and the AUR version breaks whenever a Ruby library gets updated. This happened today, so I've taken the opportunity to try a different tmux session helper.
#tmuxp is a Python tmux session manager. Also, it's in Arch's repos so shouldn't break on an update.
It does a weird thing where every command it sends to a pane is prefixed by a space - this could be me, but I can't work out what I'm doing wrong. Other than this weird quirk, it works great.