anchor.diff:  
             passthru = {
               enabledExtensions = [];
  -            inherit buildEnv withExtensions;
  +            buildEnv = mkBuildEnv {};
  +            withExtensions = mkWithExtensions {};
               inherit (php-packages) packages extensions;
             };
   
  
positive.code:           phpWithExtensions = self.withExtensions defaultPhpExtensions;
          });
  
          buildEnv = lib.makeOverridable (
            { extensions ? (_: []), extraConfig ? "", ... }@innerArgs:
              let
                filteredInnerArgs = builtins.removeAttrs innerArgs [ "extensions" "extraConfig" ];
                allArgs = args // filteredInnerArgs;
                php = generic allArgs;
  
                php-packages = (callPackage ../../../top-level/php-packages.nix {
                  inherit php phpWithExtensions;
  
negative.code:             in
                phpWithExtensions);
  
          mkWithExtensions = prevArgs: extensions:
            mkBuildEnv prevArgs { inherit extensions; };
  
          pcre' = if (lib.versionAtLeast version "7.3") then pcre2 else pcre;
        in
  