http://c25o7knygjm3m67jy27yuynvv4pkfi25naucscmh4ubq2ggiig3v57ad.onion/en/guix-on-an-arm-board.html
A bootloader is a structure that has a name,
a package, an installer, a configuration file and a configuration file generator. Fortunately,
Guix already defines a base u-boot bootloader, so we can inherit from it and only redefine a few
things. The Cubietruck happens to be based on an allwinner core, for which there is already a
u-boot bootloader definition u-boot-allwinner-bootloader .