anchor.diff:  
       let php7 = lib.versionAtLeast version "7.0";
           mysqlHeaders = mysql.lib.dev or mysql;
  +        mysqlndSupport = config.php.mysqlnd or false;
  +        mysqlBuildInputs = if mysqlndSupport then [] else [ mysqlHeaders ];
   
       in composableDerivation.composableDerivation {} (fixed: {
   
  
positive.code:         };
  
          mysql = {
            configureFlags = ["--with-mysql"];
            buildInputs = [ mysqlHeaders ];
          };
  
          mysqli = {
            configureFlags = ["--with-mysqli=${mysqlHeaders}/bin/mysql_config"];
            buildInputs = [ mysqlHeaders ];
          };
  
          mysqli_embedded = {
  
negative.code:         };
  
          pdo_mysql = {
            configureFlags = ["--with-pdo-mysql=${if mysqlndSupport then "mysqlnd" else mysqlHeaders}"];
            buildInputs = mysqlBuildInputs;
          };
  
          bcmath = {
  