Create a rootfs for a different architecture?

[typecasto]

Is it possible to create an arm64 rootfs on an amd64 host? currently I'm trying to build inside a docker container but I'm having a bit of trouble with that.
To avoid the XY problem, my ultimate goal is to create a root filesystem for another device (a nvidia jetson nano, it doesn't boot traditionally and so I can't install alpine normally) that it will eventually boot from. Kernel and initrd generation are handled elsewhere, so no need to worry about that, but the rootfs nvidia provides is ~10G and I'd like to use alpine instead, only problem right now is generating a rootfs for the other device to boot from.

[svmhdvn]

Any updates on this issue or #19? I'm trying to make a minimal rootfs for the pinebook pro. Currently only postmarketOS publishes SD card images for the PBP. I'd like to build a custom linux kernel with no initramfs (i.e. all modules and firmware built into the kernel binary) and use it along with a minimal rootfs on the SD card.

[typecasto]

Nothing I've heard, we ultimately went with an arm docker container running in qemu-user for a while before deciding debian suited our needs better anyway.

[gavrilyak]

The script can create rootfs for any supported arch, e.g. for arm

export ARCH=armv7  APK_OPTS="--arch $ARCH" KEYS_DIR=keys/for/armv7/packages
alpine-make-rootfs

qemu-user-static and qemu-user-static-binfmt needs to be installed for chroot

This issue can be closed, script already works perfectly fine