anchor.diff:  
           # useful tools
           ag
  +        awscli
           cloc
           cmake
           ctags
  
positive.code:       wreq
      ]);
  
      myPythonEnv = self.myEnvFun {
        name = "mypython3";
        buildInputs = [
          python3
          python3Packages.matplotlib
        ];
      };
  
      # build emacs from source
      emacs-master = pkgs.stdenv.lib.overrideDerivation pkgs.emacs (oldAttrs: {
  
negative.code:       paths = [
          libmikey
          myHaskellEnv
          myPython3Env
          cabal2nix
  
          diagrams-builder
  