anchor.diff:  
         nativeBuildInputs =
           [ pkgconfig ]
  -        ++ lib.optionals is30
  +        ++ lib.optionals is24
             [ autoreconfHook
               autoconf-archive
               bison flex
  
positive.code:             patchelf --set-rpath $out/lib:${stdenv.cc.cc.lib}/lib $out/lib/libboost_thread.so.*
            ''}
          '' +
          # For Nix 3.0, patch around an issue where the Nix configure step pulls in the
          # build system's bash and other utilities when cross-compiling
          lib.optionalString (stdenv.buildPlatform != stdenv.hostPlatform && isExactly30) ''
            mkdir tmp/
            substitute corepkgs/config.nix.in tmp/config.nix.in \
              --subst-var-by bash ${bash}/bin/bash \
  
negative.code:       inherit name src;
        version = lib.getVersion name;
  
        is24 = lib.versionAtLeast version "2.4pre";
        isExactly24 = lib.versionAtLeast version "2.4" && lib.versionOlder version "2.4";
  
        VERSION_SUFFIX = suffix;
  
  