Operation systems that still not use systemd probably use upstart.

Here is example script, e.g. /etc/init/yourapp.conf:

description "your app description"
start on runlevel [2345]
stop on runlevel [06]

respawn

exec bash /srv/yourapp/run.sh

Sh script: /srv/yourapp/run.sh

#!/bin/bash

# you can do some actions here
# and start daemon process e.g.:
uwsgi --ini /srv/yourapp/uwsgi.ini

Then you can do:

Start Stop Restart
service yourapp start service yourapp stop service yourapp restart