anchor.diff:            config.allowUnfree = true;
           };
           arm64Impure = arm64 // {
  +          inherit system;
             crossSystem = arm64.crossSystem // { useAndroidPrebuilt = true; };
           };
           armv7a = {
  +          inherit system;
             crossSystem = {
               config = "arm-unknown-linux-androideabi";
               arch = "armv7";
  
positive.code:             };
          in {
          simulator64 = nixpkgsFunc {
            crossSystem = {
              # You can change config/arch/isiPhoneSimulator depending on your target:
              # aarch64-apple-darwin14 | arm64  | false
  
negative.code:           inherit config;
          };
          arm64 = nixpkgsFunc {
            inherit system;
            crossSystem = {
              # You can change config/arch/isiPhoneSimulator depending on your target:
              # aarch64-apple-darwin14 | arm64  | false
  