anchor.diff:  
   rustPlatform.buildRustPackage rec {
     pname = "cargo-make";
  -  version = "0.19.5";
  +  version = "0.20.0";
   
     src =
       let
  
positive.code:         owner = "sagiegurari";
          repo = pname;
          rev = version;
          sha256 = "0xjyzsi3n3lb5g4gl6v0s4p87nazkqgjf244m792iji9i568ynjb";
        };
        cargo-lock = fetchurl {
          url = "https://gist.githubusercontent.com/xrelkd/e4c9c7738b21f284d97cb7b1d181317d/raw/285cf8f9b0ab33db0d656fdc8e759feed55c0167/cargo-make-Cargo.lock";
          sha256 = "0l2i2hq43k482m2w6hpapaq53r8bjljfcszp6csljj4fvxcl62yj";
        };
      in
      runCommand "cargo-make-src" {} ''
  
negative.code: 
    buildInputs = stdenv.lib.optionals stdenv.isDarwin [ Security ];
  
    cargoSha256 = "1r2fiwcjf739rkprrwidgsd9i5pjgk723ipazmlccz2jpwbrk7zr";
  
    # Some tests fail because they need network access.
    # However, Travis ensures a proper build.
  