my-daemon.service

# put me in /etc/systemd/system/my-daemon.service
# chmod 644 /etc/systemd/system/my-daemon.service

# more on systemd folders (lib vs etc) here: https://www.digitalocean.com/community/tutorials/understanding-systemd-units-and-unit-files

[Service]
ExecStart=/home/seb/code/systemd-stdout/my-daemon.sh