anchor.diff:  
   buildPythonPackage rec {
     pname = "nmigen";
  -  version = "unstable-2019-10-17";
  +  version = "unstable-2019-02-08";
     # python setup.py --version
  -  realVersion = "0.1.rc2.dev5+g${lib.substring 0 7 src.rev}";
  +  realVersion = "0.2.dev49+g${lib.substring 0 7 src.rev}";
   
     src = fetchFromGitHub {
  -    owner = "m-labs";
  +    owner = "nmigen";
       repo = "nmigen";
  -    rev = "9fba5ccb513cfbd53f884b1efca699352d2471b9";
  -    sha256 = "02bjry4sqjsrhl0s42zl1zl06gk5na9i6br6vmz7fvxic29vl83v";
  +    rev = "66f4510c4465be5d0763d7835770553434e4ee91";
  +    sha256 = "19y39c4ywckm4yzrpjzcdl9pqy9d1sf1zsb4zpzajpmnfqccc3b0";
     };
   
     disabled = pythonOlder "3.6";
   
     nativeBuildInputs = [ setuptools_scm ];
   
  -  propagatedBuildInputs = [ setuptools pyvcd bitarray jinja2 ];
  +  propagatedBuildInputs = [ setuptools pyvcd jinja2 ];
   
     checkInputs = [ yosys symbiyosys yices ];
   
  
positive.code: , setuptools
  , setuptools_scm
  , pyvcd
  , bitarray
  , jinja2
  
  # for tests
  
negative.code: 
    meta = with lib; {
      description = "A refreshed Python toolbox for building complex digital hardware";
      homepage = https://github.com/nmigen/nmigen;
      license = licenses.bsd2;
      maintainers = with maintainers; [ emily ];
    };
  }
  