mount -o loop vbdev/Partition1 vbmnt
# remove cruft
+#xapian indices
+find vbmnt/var/ -wholename '*xapian*.DB' -delete
# package cache
find vbmnt/var/cache/apt/archives/ -name '*.deb' -delete
rm -f vbmnt/var/cache/apt/*.bin
find vbmnt/var/lib/apt -type f -name '*debian*' -o -type f -name '*list*' -delete
# user data
# cannot clean all root stuff, because it also contains useful thing (e.g. git setup)
-#find vbmnt/root -mindepth 1 -delete
rm -f vbmnt/root/.*history
-# everything for the default user
-find vbmnt/home/brain -mindepth 1 -delete
+rm -f vbmnt/home/brain/.*history vbmnt/home/brain/nd*
# unmount filesystem
umount vbmnt