Serving a Nix store via SSH You can tell Nix to automatically fetch needed binaries from a remote Nix store via SSH. For example, the following installs Firefox, automatically fetching any store paths in Firefox’s closure if they are available on the server avalon: $ nix-env -i firefox --substituters ssh://alice@avalon This works similar to the binary cache substituter that Nix usually uses, only using SSH instead of HTTP: if a store path P is needed, Nix will first check if it’s available in the Nix store on avalon. If not, it will fall back to using the binary cache substituter, and then to building from source. The SSH substituter currently does not allow you to enter an SSH passphrase interactively. Therefore, you should use ssh-add to load the decrypted private key into ssh-agent. You can also copy the closure of some store path, without installing it into your profile, e.g. $ nix-store -r /nix/store/m85bxg…-firefox-34.0.5 --substituters ssh://alice@avalon This is essentially equivalent to doing $ nix-copy-closure --from alice@avalon /nix/store/m85bxg…-firefox-34.0.5 You can use SSH’s forced command feature to set up a restricted user account for SSH substituter access, allowing read-only access to the local Nix store, but nothing more. For example, add the following lines to sshd_config to restrict the user nix-ssh: Match User nix-ssh AllowAgentForwarding no AllowTcpForwarding no PermitTTY no PermitTunnel no X11Forwarding no ForceCommand nix-store --serve Match All On NixOS, you can accomplish the same by adding the following to your configuration.nix: nix.sshServe.enable = true; nix.sshServe.keys = [ "ssh-dss AAAAB3NzaC1k... bob@example.org" ]; where the latter line lists the public keys of users that are allowed to connect.