A terminal based Pomodoro coountdown doesn’t appear to exist but can be created simply in i3’s config file.
It requires the following packages to enable “notify-send” which is a simple gtk popup notification.
# Pomodoro start and end notifications
bindsym $mod+Control+p exec notify-send --icon=gtk-info Pomodoro "Focus for 25 minutes" && sleep 2500 && notify-send --icon=gtk-info Pomodoro "Take a 5 minute break"
This quick notification will dismiss itself in a few seconds, if you blink you may miss it.
As an alternative I’m also considering adding my bash command to lock the system and force that me to at least put in my password to continue.