anchor.diff:          # Show some output while running tests, so we might notice what's wrong
           testTarget = "--show-details=streaming";
   
  -        testHaskellDepends = (drv.testHaskellDepends or []) ++ stdenv.lib.optionals (!noGcTest) [
  +        testHaskellDepends = with haskellPackages; (drv.testHaskellDepends or []) ++ stdenv.lib.optionals (!noGcTest) [
             temporary
             jsaddle-warp
             process
             chrome-test-utils
           ];
   
  -        testSystemDepends = (drv.testSystemDepends or []) ++ [
  +        testSystemDepends = with pkgs; (drv.testSystemDepends or []) ++ [
             selenium-server-standalone which
           ] ++ stdenv.lib.optionals (!noGcTest) [
             chromium
  
positive.code:   inherit (pkgs) stdenv;
    haskellLib = pkgs.haskell.lib;
  in {
    reflex-dom-core = haskellPackages.callPackage
      ({ temporary, jsaddle-warp, process, chrome-test-utils
       , selenium-server-standalone, which, fontconfig, chromium, pkgs
       }: let
        inherit (haskellPackages) ghc;
        noGcTest = stdenv.hostPlatform.system != "x86_64-linux"
                || stdenv.hostPlatform != stdenv.buildPlatform
  
negative.code:       } // stdenv.lib.optionalAttrs (!noGcTest) {
          # The headless browser run as part of gc tests would hang/crash without this
          preCheck = ''
            export FONTCONFIG_PATH=${pkgs.fontconfig.out}/etc/fonts
          '';
        });
    reflex-dom = haskellLib.overrideCabal
        (haskellPackages.callCabal2nix "reflex-dom" ./reflex-dom { })
        (drv: {
          # Hack until https://github.com/NixOS/cabal2nix/pull/432 lands
          libraryHaskellDepends = (drv.libraryHaskellDepends or []) ++ stdenv.lib.optionals (with stdenv.hostPlatform; isAndroid && is32bit) [
            haskellPackages.android-activity
          ];
        });
    chrome-test-utils = haskellPackages.callCabal2nix "chrome-test-utils" ./chrome-test-utils {};
  }
  