anchor.diff:        with C-style syntax. It offers compilation to JavaScript, interfaces,
         mixins, abstract classes, reified generics, and optional typing.
       '';
  -    platforms = [ "x86_64-linux" "i686-linux" "aarch64-linux" ];
  +    platforms = [ "x86_64-linux" "i686-linux" "aarch64-linux" "x86_64-darwin" ];
       license = licenses.bsd3;
     };
   }
  
positive.code:       url = "${base}/${stable_version}/release/${version}/sdk/dartsdk-linux-${aarch64}-release.zip";
        sha256 = "1p66fkdh1kv0ypmadmg67c3y3li3aaf1lahqh2g6r6qrzbh5da2p";
      };
      "2.10.0-x86_64-linux" = fetchurl {
        url = "${base}/${stable_version}/release/${version}/sdk/dartsdk-linux-${x86_64}-release.zip";
        sha256 = "0dncmsfbwcn3ygflhp83i6z4bvc02fbpaq1vzdzw8xdk3sbynchb";
      };
      "2.9.0-4.0.dev-x86_64-linux" = fetchurl {
        url = "${base}/${dev_version}/release/${version}/sdk/dartsdk-linux-${x86_64}-release.zip";
  
negative.code:     "2.9.0-4.0.dev-aarch64-linux" = fetchurl {
        url = "${base}/${dev_version}/release/${version}/sdk/dartsdk-linux-${aarch64}-release.zip";
        sha256 = "1x6mlmc4hccmx42k7srhma18faxpxvghjwqahna80508rdpljwgc";
      };
      "2.11.0-161.0.dev-x86_64-darwin" = fetchurl {
        url = "${base}/${dev_version}/release/${version}/sdk/dartsdk-macos-${x86_64}-release.zip";
        sha256 = "0mlwxp7jkkjafxkc4vqlgwl62y0hk1arhfrvc9hpm9dv98g3bdjj";
      };
      "2.11.0-161.0.dev-x86_64-linux" = fetchurl {
        url = "${base}/${dev_version}/release/${version}/sdk/dartsdk-linux-${x86_64}-release.zip";
  