PortMidi on RPi

[type1fool]

PortMidi works well on my host, but it's not functional on my Nerves RPi. I get this error when I try PortMidi.devices on the pi:

{:load_failed, 'Failed to load NIF library: \'srv/erlang/lib/portmidi-5.1.1/priv/portmidi_devices.so: invalid ELF header\''}

I'm just getting started with Nerves, and I'm not familiar with make. @ConnorRigby pointed to cross compilation here: https://github.com/nerves-project/dhcp_server/blob/master/Makefile

Thank you.