[systemd-devel] Execute custom command whenever network interface appears

[DimanNe]

Hello,
I read manual about systemd-networkd module (http://www.freedesktop.org/software/systemd/man/systemd.network.html), and as far as I know, I can do only basic actions (like run dhcp, or assign static addresses/mac/routes and so on), but in general I want to run some script or command.

Here is real world example - https://wiki.archlinux.org/index.php/ZTE_MF_823_(Megafon_M100-3)_4G_Modem
If you are using usb modem, you should
1) run dhcp
2) run curl/wget with special url

so, my question, it it possible just now (how?)? If not, what is the best approach to accomplish described above task?