anchor.diff:  , stdenv
   , symlinkJoin
   , fetchFromGitHub
  +, libxcrypt
   }:
   
   let
  
positive.code:     inherit mkSubProject;
      wiringPi = mkSubProject {
        subprj = "wiringPi";
      };
      devLib = mkSubProject {
        subprj = "devLib";
  
negative.code:     gpio = mkSubProject {
        subprj = "gpio";
        buildInputs = [
          libxcrypt
          passthru.wiringPi
          passthru.devLib
        ];
  