anchor.diff:  
     # https://github.com/ndmitchell/shake/issues/206
     # https://github.com/ndmitchell/shake/issues/267
  -  shake = overrideCabal super.shake (drv: { doCheck = !pkgs.stdenv.isDarwin && false; });
  +  shake = overrideCabal super.shake (drv: { });
   
     # https://github.com/nushio3/doctest-prop/issues/1
     doctest-prop = dontCheck super.doctest-prop;
  
positive.code:   options_1_2 = dontCheck super.options_1_2;
    options = dontCheck super.options;
    statistics = dontCheck super.statistics;
    c2hs = if pkgs.stdenv.isDarwin then dontCheck super.c2hs else super.c2hs;
  
    # The package doesn't compile with ruby 1.9, which is our default at the moment.
    hruby = super.hruby.override { ruby = pkgs.ruby_2_1; };
  
negative.code:   # https://github.com/yesodweb/serversession/issues/1
    serversession = dontCheck super.serversession;
  
    yesod-bin = super.yesod-bin;
  
    hmatrix = super.hmatrix;
  
    # https://github.com/commercialhaskell/stack/issues/408
    # https://github.com/commercialhaskell/stack/issues/409
  