gentoo-overlay/net-im/coturn/files/coturn.service

[Unit]
Description=turnserver daemon
After=networking.target

[Service]
Type=simple
User=turnserver
Group=turnserver
PermissionsStartOnly=true
ExecStartPre=/bin/bash -c "[ -f /var/log/turnserver.log ] || touch /var/log/turnserver.log && chown turnserver:turnserver /var/log/turnserver.log && chmod 660 /var/log/turnserver.log"
ExecStart=/usr/bin/turnserver --pidfile /var/run/turnserver/turnserver.pid
Restart=always
RestartSec=30s

[Install]
WantedBy=multi-user.target