I’ve preordered my Photon few weeks ago and started wondering if micro Linux would run on it: μClinux
Teoretically 1MB of flash memory should be enough for very simple kernel compilation. 128KB of RAM is not enough for sure but connecting external RAM chip (Is it possible?) should make it possible.
I guess that it would not be practical, but being able to SSH into Photon board would be very cool.
Here is an article about minimal requirements of uclinux on microcontrollers: https://www.emcraft.com/stm32f429discovery/what-is-minimal-footprint