This is useful if your local machine is powerful and you have built a number of packages on it, but want to re-use them on another machine, without using a Nix cache or rebuilding them.
nix copy --to ssh-ng://admin@100.96.121.13 /nix/store/???If you use nixci, this looks like:
nixci . -- --option system aarch64-linux | xargs nix copy --to ssh-ng://admin@100.96.121.13