Trying to set up my Pinebook Pro with my favorite distribution i found out that the usual way (invoking `guix system image gnu/system/images/pinebook-pro.scm` to build an image which is then dd'd to a micro SD card) does not yield a working result.
Doing the same with guix time-machine on commit c9c195936d128465030bc05f8c319367602c93b5 generates a bootable image. Since building with a current checkout does not yield a bootable image (the pinebooks gracefully falls back to boot from the eMMC memory with its pre-installed Manjaro) I guess the bootloader broke.