anchor.diff:    inherit (nixpkgs) fetchFromGitHub writeScriptBin cpio wget;
     # nixpkgs functions used to regulate Haskell overrides
     inherit (nixpkgs.haskell.lib)
  -    dontCheck overrideCabal doJailbreak doCoverage;
  +    dontCheck overrideCabal doJailbreak doCoverage doHaddock;
     ghciDatabrary = writeScriptBin "ghci-databrary" ''
       if [ ! -d "solr-6.6.0" ]; then
         if [ ! -d "/tmp/solr-6.6.0" ]; then
  
positive.code:   pkgs = reflex-platform.ghc.override {
      overrides = self: super: rec {
        databrary =
          (if coverage then doCoverage else id)
            (self.callPackage ./databrary.nix {
              inherit postgresql nodePackages coreutils;
              # ffmpeg override with with --enable-libfdk-aac and --enable-nonfree flags set
              ffmpeg = nixpkgs.ffmpeg-full.override {
                nonfreeLicensing = true;
                fdkaacExtlib = true;
              };
            });
        # cabal override to enable ghcid (GHCi daemon) development tool
        databrary-dev = overrideCabal databrary (drv: {
          libraryHaskellDepends = (drv.libraryHaskellDepends or []) ++ (with self; [ghcid cabal-install ghciDatabrary]);
  
negative.code: { coverage ? false
  , haddock ? false
  }:
  
  let
  