anchor.diff:  , zlib
   , dbus
   , networkmanager
  -, enableJavaScript ? stdenv.isDarwin || lib.meta.availableOn stdenv.hostPlatform spidermonkey_68
  -, spidermonkey_68
  +, enableJavaScript ? stdenv.isDarwin || lib.meta.availableOn stdenv.hostPlatform spidermonkey_78
  +, spidermonkey_78
   , pcre
   , gsettings-desktop-schemas
   , glib
  
positive.code: , JavaScriptCore
  }:
  
  let
    jsRuntime = if stdenv.hostPlatform.isDarwin then JavaScriptCore else spidermonkey_68;
  in stdenv.mkDerivation rec {
    pname = "libproxy";
    version = "0.4.17";
  
  
negative.code:     python3
      zlib
    ] ++ lib.optionals enableJavaScript [
      (if stdenv.hostPlatform.isDarwin then JavaScriptCore else spidermonkey_78)
    ] ++ (if stdenv.hostPlatform.isDarwin then [
      SystemConfiguration
      CoreFoundation
  