{ pkgs, lib, ... }: {
  home-manager.users.fhauser.programs.ssh = let
    forceIdentityThreema = {
      identityFile = toString (pkgs.writeText "fabian.hauser@threema.ch.pub" ''
        ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIO7h492sXT7zdamf+nbOt+y6jiqxicOnm6+wiuEG1EvZ openpgp:0x18B553DD
      '');
      identitiesOnly = true;
    };
    forceIdentityPrivate = {
      identityFile = toString (pkgs.writeText "fabian.hauser@qo.is.pub" ''
        ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDIPF8ZV7vhpbVvLxiKq8ANVusNUHMbtii5MuvjxCbVz7vSNVPo9OOLvYyDqhbRAWMTdQeGZVAaALBufKKmprDTRFMpnA7Ut4TFrdz/5DTaR2KEjJ7P75moH+0xooR/GsbzFGsNBSQSXK3u1igndPYEC/PqCHN++32kDo2wLqTB4VLrEovU3iq8BMckn329Bu1fGbXKTgDpEvUEEwFO2brQZLMmzILGF/v4B9ImEGtinAUNgDSfEpgPN23sdWQH9rwEClGv95JmWNf05tuVomhZzOBtCFoAno3XB1nj16avjsqJ3aGFY2CCcfsNrwKzhIotmm82bcI4BJuJIVRIKbZ1 cardno:000610954665
      '');
      identitiesOnly = true;
    };
  in {
    enable = true;
    matchBlocks = {
      "work.github.com" = forceIdentityThreema // {
        hostname = "github.com";
        user = "git";
      };
      "github.com" = forceIdentityPrivate // { user = "git"; };
    };
    #TODO: Authorized keys implementation, see https://github.com/nix-community/home-manager/pull/9
  };
}