Proto-Nixops Makefile

.PHONY: hostname
hostname:
    drv=$$(nix-build --no-out-link --expr "\
        let \
            nixos = import <nixpkgs/nixos> { configuration = \
                import host/$@/configuration.nix; }; \
        in nixos.system") && \
        nix-copy-closure --use-substitutes --to "$@" "$${drv}" && \
        ssh -t "$@" "trap '' HUP && sudo sh -c \
            'nix-env -p /nix/var/nix/profiles/system --set "$${drv}" && \
            "$${drv}"/bin/switch-to-configuration switch'"
    ssh "$@" readlink -f /run/{booted,current}-system{,/kernel}