anchor.diff:    shellHook = ''
       export NIXSHELL="$NIXSHELL\[PeaCoq\]"
       export SSL_CERT_FILE="/etc/ssl/certs/ca-bundle.crt"
  -    eval `opam config env`
       echo -e "\nRemember to run setup.sh again\n"
       # ./setup.sh
     '';
  
positive.code:     #snap-server
      #snap
      peacoq-server
    ]);
    nativeBuildInputs = (with nixpkgs; [
      zlib
      zlibStatic
  
negative.code:     #cabal-install
      #coq_8_5
      ghc
      # gnome3.gtk
      haskellPackages.zlib
      nodejs
      zlib
      zlibStatic
  
  