[Unit]
Description=VBox Virtual Machine %i Service
Requires=systemd-modules-load.service
After=systemd-modules-load.service

[Service]
User=username
Group=vboxusers
ExecStart=/usr/bin/VBoxManage startvm %i --type headless
ExecStop=/usr/bin/VBoxManage controlvm %i savestate
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target