{...}: let
  usb_data = import ../data/usb_data.nix {};
in {
  programs.ssh.matchBlocks."*".identityFile = "${usb_data.ssh_priv_path}";
  programs.git.extraConfig = {
    gpg.format = "ssh";
    commit.gpgsign = "true";
    tag.gpgsign = "true";
    user = {signingKey = "${usb_data.ssh_priv_path}";};
  };
}