With release of systemd version 216, a number of bugs were corrected and configurations options added related to bonding support in systemd-networkd.

Here’s a basic example on setting up bonding in systemd:

/etc/systemd/network/bond0.network:

[Match]
Name=enp1*

[Network]
Bond=bond0

You can also specify the interfaces like enp1s0f[01] if you need to be more specific.

/etc/systemd/network/bond0.netdev:

[NetDev]
Name=bond0
Kind=bond

[Bond]
Mode=802.3ad
LACPTransmitRate=fast
MIIMonitorSec=1s
UpDelaySec=2s
DownDelaySec=8s

/etc/systemd/network/Management.network:

[Match]
Name=bond0

[Network]
Address=192.168.20.20/24
Gateway=192.168.20.1
DNS=8.8.8.8

Enable and start systemd-networkd:

systemctl enable systemd-networkd
systemctl start systemd-networkd

For more options, make sure to check out the systemd.network and systemd.netdev man pages.