appname.rb

window "AppName" do
  root "~/dev/thoughtbot/app"

  vpane 75, "vim ."
  vpane 25 do
    hpane 75
    hpane 25 do
      vpane 50, "guard"
      vpane 50, "evergreen serve"
    end
  end
end

appname.sh

#!/bin/sh

tmux new-window -n AppName

tmux split-window -p25 -t0 -dv
tmux split-window -p25 -t1 -dh
tmux split-window -p50 -t2 -dv

tmux send-keys -t 0 "cd ~/dev/thoughtbot/app" C-m
tmux send-keys -t 1 "cd ~/dev/thoughtbot/app" C-m
tmux send-keys -t 2 "cd ~/dev/thoughtbot/app" C-m
tmux send-keys -t 3 "cd ~/dev/thoughtbot/app" C-m

tmux send-keys -t 0 "vim ." C-m
tmux send-keys -t 2 "guard" C-m
tmux send-keys -t 3 "evergreen serve" C-m