Build raspberry pi arm64 docker images faster on desktop using buildx

So apparently, it was already possible for quite a while to build docker images cross platform , but I only recently found out. This is extremely useful to create docker images for raspberry pi's because building docker images on the device itself takes a really long time. Docker uses the buildx command, with the x behind build referring to "experimental".

You can create and switch to the experimental builder with these commands

docker buildx create --name mybuilder
docker buildx use mybuilder

After switching you can use the buildx build command and specify the platform using --platform linux/arm64 to build an image for that specific platform. In this example, I tag and push the image to the repository in the same command:

docker buildx build --platform linux/arm64 -t peterpeerdeman/docker-prophet-arm:1.0.0-slim --push .