How to create a systemd service.
A simple unit file in /etc/systemd/system will provide a systemd compatible service on a linux system.
For example /etc/systemd/helloworld.service:
[Unit]
Description=Hello World Service
After=multi-user.target
[Service]
Type=simple
ExecStart=/usr/local/sbin/helloworldd start
ExecStop=/usr/local/sbin/helloworldd stop
TimeoutStopSec=infinity
[Install]
WantedBy=multi-user.target