I've been leveraging docker buildx to create multi architecture images for a few months. It's quite nice and simple, and I've been able to even automate the multiarch builds with GitHub Actions. See an example repo of mine here: https://github.com/jmb12686/docker-cadvisor
Here's another repo of mine doing (essentially) the same thing, multi arch image build using GitHub Actions. There is a bit more documentation in this repo regarding local builds though: https://github.com/jmb12686/node-exporter
