anchor.diff:  
             inkscape
   
  -          blender
  +          # blender
             librecad
           ];
         };
  
positive.code: { config, lib, pkgs, ... }:
  
  let
   #  myclojureenv = pkgs.myEnvFun {
   #    name = "clojure";
   #    buildInputs = with pkgs; [
   #      leiningen clojure
   #    ];
   #  };
   #  mypythonenv = pkgs.myEnvFun {
   #    name = "python";
   #    buildInputs = with pkgs; [
   #      python python3 python35Packages.bpython
   #    ];
   #  };
   #  myrubyenv = pkgs.myEnvFun {
   #    name = "ruby";
   #    buildInputs = with pkgs; [
   #      ruby
   #    ];
   #  };
   #  myschemeenv = pkgs.myEnvFun {
   #    name = "scheme";
   #    buildInputs = with pkgs; [
   #      chicken
   #    ];
   # };
   # myrustenv = pkgs.myEnvFun {
   #   name = "rust";
   #     buildInputs = with pkgs; [
   #       rustc
   #   ];
   # };
  
  in {
    options = {
      myconfig.roles.work = {
        enable = lib.mkEnableOption "Work role";
  
negative.code:           meld
            unstable.stack unstable.cabal-install unstable.cabal2nix
            gnumake cmake automake
            cloc
            gitAndTools.gitFull
            gitAndTools.tig
          ] ++ (with pkgs.unstable.haskellPackages; [
  