nix-copy-closure 1 Nix nix-copy-closure copy a closure to or from a remote machine via SSH nix-copy-closure --to --from --sign --gzip --include-outputs --use-substitutes -s user@machine paths nix-copy-closure gives you an easy and efficient way to exchange software between machines. Given one or more Nix store paths paths on the local machine, nix-copy-closure computes the closure of those paths (i.e. all their dependencies in the Nix store), and copies all paths in the closure to the remote machine via the ssh (Secure Shell) command. With the --from, the direction is reversed: the closure of paths on a remote machine is copied to the Nix store on the local machine. This command is efficient because it only sends the store paths that are missing on the target machine. Since nix-copy-closure calls ssh, you may be asked to type in the appropriate password or passphrase. In fact, you may be asked twice because nix-copy-closure currently connects twice to the remote machine, first to get the set of paths missing on the target machine, and second to send the dump of those paths. If this bothers you, use ssh-agent. --to Copy the closure of paths from the local Nix store to the Nix store on machine. This is the default. --from Copy the closure of paths from the Nix store on machine to the local Nix store. --sign Let the sending machine cryptographically sign the dump of each path with the key in sysconfdir/nix/signing-key.sec. If the user on the target machine does not have direct access to the Nix store (i.e., if the target machine has a multi-user Nix installation), then the target machine will check the dump against sysconfdir/nix/signing-key.pub before unpacking it in its Nix store. This allows secure sharing of store paths between untrusted users on two machines, provided that there is a trust relation between the Nix installations on both machines (namely, they have matching public/secret keys). --gzip Enable compression of the SSH connection. --include-outputs Also copy the outputs of store derivations included in the closure. --use-substitutes / -s Attempt to download missing paths on the target machine using Nix’s substitute mechanism. Any paths that cannot be substituted on the target are still copied normally from the source. This is useful, for instance, if the connection between the source and target machine is slow, but the connection between the target machine and nixos.org (the default binary cache server) is fast. NIX_SSHOPTS Additional options to be passed to ssh on the command line. Copy Firefox with all its dependencies to a remote machine: $ nix-copy-closure --to alice@itchy.labs $(type -tP firefox) Copy Subversion from a remote machine and then install it into a user environment: $ nix-copy-closure --from alice@itchy.labs \ /nix/store/0dj0503hjxy5mbwlafv1rsbdiyx1gkdy-subversion-1.4.4 $ nix-env -i /nix/store/0dj0503hjxy5mbwlafv1rsbdiyx1gkdy-subversion-1.4.4