Build `aarch64` Docker image on `amd64` machine

[peterbecich]

I am piecing this together here:

How to configure QEMU binfmt wrapper on a non-NixOS machine

Hi group, I want to build aarch64 packages using a remote builder. I have a non-aarch64 machine baseline configured as a remote builder, meaning I can just run ssh builder nix-store --version. The machine does not have NixOS installed but nix and nix-daemon running. I am stuck with where to add boot.binfmt.emulatedSystems = [ "aarch64-linux" ]; equivalent as I have no configuration.nix. Do I have to set up a qemu vm with NixOS inside ?

and here: Cross-building for aarch64 with Nix on a non-NixOS (Fedora 39) machine won't use the cache - #7 by ElvishJerricco