Setup as a service on Linux using systemd

Create a file called /etc/systemd/system/r53-ddns.service as root.

[Unit]
Description=R53 DDNS Service
After=network.target
StartLimitIntervalSec=0

[Service]
Type=simple
Restart=always
RestartSec=1
User=root
ExecStart=/snap/bin/r53-ddns -s=net -d=example.com -c=300

[Install]
WantedBy=multi-user.target

Set up the AWS credentials file in default location for the root user.

Start the service with the following:

sudo systemctl start r53-ddns

Make sure it restarts on reboot:

sudo systemctl daemon-reload
sudo systemctl enable r53-ddns

Check it is running OK:

systemctl status r53-ddns

Another issue you will find it that the binary snap will not update unless you stop the service. You might want to consider putting something like this in the crontab of your root user which will keep all of your :

0 0 0 * * service r53-ddns stop && snap refresh r53-ddns && service r53-ddns start