anchor.diff: -{ stdenv, fetchurl, pkgconfig
  -, systemd ? null
  +{ stdenv
  +, fetchurl
  +
  +, systemd_lib
   }:
   
   stdenv.mkDerivation rec {
  
positive.code:     sha256 = "02w94j344q0ywlj4mdf9fnzwggdsn3j1yn43sdlsddvr29lw239i";
    };
  
    buildInputs = [ pkgconfig systemd ];
  
    configureFlags = [
      "--enable-rfc3195"
      "--enable-stdlog"
      (if systemd != null then "--enable-journal" else "--disable-journal")
      "--enable-man-pages"
    ];
  
  
negative.code:     homepage = http://www.liblogging.org/;
      description = "Lightweight signal-safe logging library";
      license = licenses.bsd2;
      maintainers = with maintainers; [
        wkennington
      ];
      platforms = with platforms;
        x86_64-linux;
    };
  }
  