anchor.diff:    # Generate the NixOS manpages.
     manpages = runCommand "nixos-manpages"
       { inherit sources;
  -      buildInputs = [ libxml2 libxslt ];
  +      nativeBuildInputs = [ buildPackages.libxml2 buildPackages.libxslt ];
         allowedReferences = ["out"];
       }
       ''
  
positive.code:   # Generate the NixOS manual.
    manual = runCommand "nixos-manual"
      { inherit sources;
        buildInputs = [ libxml2 libxslt ];
        meta.description = "The NixOS manual in HTML format";
        allowedReferences = ["out"];
      }
  
negative.code: 
    olinkDB = runCommand "manual-olinkdb"
      { inherit sources;
        nativeBuildInputs = [ buildPackages.libxml2 buildPackages.libxslt ];
      }
      ''
        xsltproc \
  