ncdu on files to back up

I use borg and restic to backup files in my system. Sometimes I run a huge download or clone a large git repo and forget to mark it with CACHEDIR.TAG , and it gets picked up slowing the backup process and wasting backup space uselessly. I would like to occasionally audit the system to have an idea of what is a candidate for backup. ncdu would be great for this, but it doesn't know about backup…