nixos-config/modules/system/ssh/default.nix

{ user, ... }:
{
    services.openssh = {
        enable = true;
        settings.PasswordAuthentication = false;
        settings.KbdInteractiveAuthentication = false;
    };
    users.users.${user}.openssh.authorizedKeys.keys = [
        "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEun1YkEfxTpcsQk7ZIwuVTcSsVHjwuKA7xOW4TAi3SE mo@workstation"
    ];
}