Mbed OS FRDM-KV31F

Mbed OS supports a few NXP freedom boards. But I was looking to see if anyone has ever modified Mbed OS to compile for the FRDM-KV31F board. How difficult is it to create the board specific files?

If anyone has any experience in getting other unsupported boards to work with Mbed OS, let me know what resources are available online to being working on this. I don’t mind putting in some time this summer, but I need to get a starting point.