anchor.diff:        elpaBuild {
           pname = "buttercup";
           ename = "buttercup";
  -        version = "1.24";
  -        src = fetchurl {
  -          url = "https://elpa.nongnu.org/nongnu/buttercup-1.24.tar";
  -          sha256 = "1ch949xf03gw9r5v32akx7hqnq7zrp3qr3gcic5b52yl5nmy8mhn";
  +        version = "1.25";
  +        src = fetchurl {
  +          url = "https://elpa.nongnu.org/nongnu/buttercup-1.25.tar";
  +          sha256 = "1iadgn56sfakv927g9bk7fq7yjg0f3r10ygrmjpy46vgvfz0fqs6";
           };
           packageRequires = [ emacs ];
           meta = {
  
positive.code:           license = lib.licenses.free;
          };
        }) {};
      pacmacs = callPackage ({ cl-lib ? null
                             , dash
                             , elpaBuild
                             , emacs
                             , f
                             , fetchurl
                             , lib }:
        elpaBuild {
          pname = "pacmacs";
          ename = "pacmacs";
          version = "0.1";
          src = fetchurl {
            url = "https://elpa.nongnu.org/nongnu/pacmacs-0.1.tar";
            sha256 = "0vhxxnk8n4h2klvr4xahsm845dwds895fxxgcs7dz2262g9myd93";
          };
          packageRequires = [ cl-lib dash emacs f ];
          meta = {
            homepage = "https://elpa.gnu.org/packages/pacmacs.html";
            license = lib.licenses.free;
  
negative.code:       elpaBuild {
          pname = "elpher";
          ename = "elpher";
          version = "3.3.3";
          src = fetchurl {
            url = "https://elpa.nongnu.org/nongnu/elpher-3.3.3.tar";
            sha256 = "0yaf6g424g6dngg0acbhlhd24k77bl5h82wiw98f3731xdad174r";
          };
          packageRequires = [ emacs ];
          meta = {
  