Start script for RVM + Thin + unix socket. Should be located in the project's root directory.

start.sh

#!/bin/bash
DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
sudo -u www-data touch $DIR/tmp/sockets/thin.sock
rvmsudo -u www-data bundle exec thin start -C thin.yml --socket $DIR/tmp/sockets/thin.sock

stop.sh

#!/bin/bash
rvmsudo -u www-data bundle exec thin stop

This is outdated. I recommend using runit or systemd to manage these kinds of services. Both can work in unprivileged (non-root) mode.