gentoo-overlay/sys-apps/haveged/files/service.gentoo

[Unit]
Description=Entropy Daemon based on the HAVEGE algorithm
Documentation=man:haveged(8) http://www.issihosts.com/haveged/

[Service]
Type=forking
PIDFile=/run/haveged.pid
EnvironmentFile=/etc/haveged.conf
ExecStart=/usr/sbin/haveged -w ${WATERMARK} -v 1 -p /run/haveged.pid -r 0

[Install]
WantedBy=multi-user.target