anchor.diff:  let
     cfg = config.services.public-inbox;
     stateDir = "/var/lib/public-inbox";
  -
  -  manref = name: vol: "<citerefentry><refentrytitle>${name}</refentrytitle><manvolnum>${toString vol}</manvolnum></citerefentry>";
   
     gitIni = pkgs.formats.gitIni { listsAsDuplicateKeys = true; };
     iniAtom = elemAt gitIni.type/*attrsOf*/.functor.wrapped/*attrsOf*/.functor.wrapped/*either*/.functor.wrapped 0;
  
positive.code:       args = mkOption {
          type = with types; listOf str;
          default = [];
          description = "Command-line arguments to pass to ${manref "public-inbox-mda" 1}.";
        };
      };
      postfix.enable = mkEnableOption "the integration into Postfix";
  
negative.code:       type = with types; nullOr str;
        default = null;
        example = "/path/to/fullchain.pem";
        description = lib.mdDoc "Path to TLS certificate to use for connections to {manpage}`public-inbox-${proto}d(1)`.";
      };
      key = mkOption {
        type = with types; nullOr str;
        default = null;
        example = "/path/to/key.pem";
        description = lib.mdDoc "Path to TLS key to use for connections to {manpage}`public-inbox-${proto}d(1)`.";
      };
    };
  
  