anchor.diff:    src = fetchFromGitHub {
       owner = "FiloSottile";
       repo = "age";
  -    rev = "f0f8092d60bb96737fa096c29ec6d8adb5810390";
  -    sha256 = "079kfc8d1pr39hr4qnx48kviyzwg4p8m4pz0bdkypns4aq8ppbfk";
  +    rev = "v${version}";
  +    sha256 = "0pp6zn4rdypyxn1md9ppisiwiapkfkbh08rzfl3qwn0998wx6gnb";
     };
   
     meta = with lib; {
  
positive.code: 
  buildGoModule rec {
    pname = "age";
    version = "unstable-2020-03-25";
    goPackagePath = "github.com/FiloSottile/age";
    vendorSha256 = "0km7a2826j3fk2nrkmgc990chrkcfz006wfw14yilsa4p2hmfl7m";
  
  
negative.code:     license = licenses.bsd3;
      maintainers = with maintainers; [ tazjin ];
    };
  }
  