Refer to cubicweb.readthedocs.io in README docs.cubicweb.org contains outdated documentation at the moment (and for quite some time); until it gets update, refer to the up-to-date documentation on readthedocs.

#!/bin/sh -e

if [ "$1" = "purge" ] ; then
        rm -rf /etc/cubicweb.d/
        rm -rf /var/log/cubicweb/
        rm -rf /var/lib/cubicweb/
fi

#DEBHELPER#
 
exit 0