anchor.diff:      # Python
       python  # NOTE: `python2`
       python3 # NOTE: `python` (not `python3`)
  -    python35Packages.pip
  -    python35Packages.pygments
   
       # Shell
       bash
  
positive.code:     pointfree
      pointful
      purescript
  
    ]) ++ (with pkgs.elmPackages; [
      elm
    ]);
  
    services.nix-daemon.enable = true;
  
negative.code:     # ngrok # TODO: 2.x
      # TODO: prometheus
      wget
    ]) ++ (with pkgs.elmPackages; [
      elm
    ]) ++ (with pkgs.haskellPackages; [
      cabal2nix
      # TODO: idris
  