[moreentropy]

I have some buildroot external trees on github that build images using github actions. It's for personal stuff I needed and only need to update occasionally.

The Buildroot manual is fantastic and it's worth working through the getting started section to get an idea. It boils down to creating a br_external tree that contains everything necessary to create a custom sdcard image as documented here:

https://buildroot.org/downloads/manual/manual.html#outside-b...

Building images from a br_external tree is pretty trivial, see the gitub actions in these example repos:

This builds a raspi4 64 bit image for tvheadend (I'm using this image for a SAT-IP TV dish w/ Kodi clients in my sister's house - so far no complaints about a crashed tv server after 1.5 years of uptime). This image runs the whole rootfs from initramfs w/o mounting a persistent root filesystem. I don't care for the additional ~150MB RAM that is used in this use case:

https://github.com/markuslindenberg/dvbheadend

My most recent buildroot based raspi image builds a 32 bit image pulling binary distribution of openhab and it's recommended jre into the image, running them from a read only root filesystem. I'm using this to reliably run openhab home automation in multiple places. This repo also is a br_external tree and embarrasingly doesn't have a README yet, I really really need to write one becaus I think it's quite useful and mature.

https://github.com/markuslindenberg/habfw