anchor.diff:    haskell-unicode-input-method = melpaBuild {
       pname = "emacs-haskell-unicode-input-method";
       version = "20110905.2307";
  +
       src = pkgs.fetchFromGitHub {
         owner = "roelvandijk";
         repo = "emacs-haskell-unicode-input-method";
         rev = "d8d168148c187ed19350bb7a1a190217c2915a63";
         sha256 = "09b7bg2s9aa4s8f2kdqs4xps3jxkq5wsvbi87ih8b6id38blhf78";
       };
  +
       recipe = pkgs.writeText "recipe" ''
         (emacs-haskell-unicode-input-method
          :repo "roelvandijk/emacs-haskell-unicode-input-method"
          :fetcher github)
       '';
  +
       packageRequires = [];
  +
       meta = {
         homepage = "https://melpa.org/#haskell-unicode-input-method/";
         license = lib.licenses.free;
       };
     };
  -
  -  helm-words = callPackage ./helm-words { };
  -
  -  isearch-plus = callPackage ./isearch-plus { };
  -
  -  isearch-prop = callPackage ./isearch-prop { };
  -
  -  jam-mode = callPackage ./jam-mode { };
   
     llvm-mode = trivialBuild {
       pname = "llvm-mode";
  
positive.code:   # closer to the old outdated package infra.
    #
    # Ideally this should be dropped some time during/after 20.03
    bbdb3 = self.melpaStablePackages.bbdb;
    jade = self.jade-mode;
    # scalaMode2 = null;  # No clear mapping as of now
    flymakeCursor = self.melpaStablePackages.flymake-cursor;
    cryptol = self.melpaStablePackages.cryptol-mode;
    maudeMode = self.maude-mode;
    phpMode = self.melpaStablePackages.php-mode;
    idris = self.melpaStablePackages.idris-mode;
    rainbowDelimiters = self.melpaStablePackages.rainbow-delimiters;
    colorTheme = self.color-theme;
    sbtMode = self.melpaStablePackages.sbt-mode;
    markdownMode = self.melpaStablePackages.markdown-mode;
    scalaMode1 = self.melpaStablePackages.scala-mode;
    prologMode = self.prolog-mode;
    hsc3Mode = self.hsc3-mode;
    graphvizDot = self.melpaStablePackages.graphviz-dot-mode;
    proofgeneral_HEAD = self.proof-general;
    proofgeneral = self.melpaStablePackages.proof-general;
    haskellMode = self.melpaStablePackages.haskell-mode;
    writeGood = self.melpaStablePackages.writegood-mode;
    erlangMode = self.melpaStablePackages.erlang;
    d = self.melpaStablePackages.d-mode;
    autoComplete = self.melpaStablePackages.auto-complete;
    tuaregMode = self.melpaStablePackages.tuareg;
    structuredHaskellMode = self.melpaStablePackages.shm;
    xmlRpc = self.melpaStablePackages.xml-rpc;
    emacsw3m = self.w3m;
    loremIpsum = self.lorem-ipsum;
    js2 = self.melpaStablePackages.js2-mode;
  
  }
  
negative.code:     };
    };
  
    ghc-mod = melpaBuild {
      pname = "ghc";
      version = pkgs.haskellPackages.ghc-mod.version;
  
      src = pkgs.haskellPackages.ghc-mod.src;
  
      packageRequires = [ haskell-mode ];
  
      propagatedUserEnvPkgs = [ pkgs.haskellPackages.ghc-mod ];
  
      recipe = pkgs.writeText "recipe" ''
        (ghc-mod :repo "DanielG/ghc-mod" :fetcher github :files ("elisp/*.el"))
      '';
  
      fileSpecs = [ "elisp/*.el" ];
  
      meta = {
        description = "An extension of haskell-mode that provides completion of symbols and documentation browsing";
        license = bsd3;
  