I found this page https://hub.docker.com/r/multiarch/qemu-user-static/ https://stackoverflow.com/questions/72444103/what-does-running-the-multiarch... seems to work after I 1) installed Docker itself (needs Go language from Google .. quite a beast! filled 1Gb for its own incremental rebuilds) 2) installed docker-cli from Slackbuilds 3) ran /etc/rc.d/rc docker start (different command on systemd distros) 4) ran mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc (may be already done by your startup scripts) 5) ran docker run --rm --privileged multiarch/qemu-user-static --reset -p yes -c yes 6) ran test line root@slax:~/src/appimagetool# docker run --rm -t --privileged arm64v8/ubuntu uname -m WARNING: The requested image's platform (linux/arm64/v8) does not match the detected host platform (linux/386) and no specific platform was requested aarch64 root@slax:~/src/appimagetool# for some reason it was not working as root without "privileged"! But hopefully now I can.download few more linuxes for exotic arches and look what their objcopy output looks like! So, hopefully more arches in our strange image-embedding code soon ;) Appimagetool build also worked after I added "privileged" to its script! env ARCH=x86_64 ci/build-in-docker.sh file appimagetool-x86_64.AppImage* appimagetool-x86_64.AppImage: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=9d7e67802fffc45391e9a993c33120227d1b7c78, stripped so,I am happy Slacker!