I have a mix of x86_64 and aarch64 machines and, damn, NixOS makes it so freaking easy. Most of nixpkgs works on both architectures. You can even use your machines as remote builders and/or use binfmt to transparently run/build stuff through qemu.

When I was helping out a friend with his free oracle aarch64 server, I got baffled on how ARM feels like a second class citizen on most distros.