diff --git a/pkgs/development/libraries/qt-5/modules/qtwebengine.nix b/pkgs/development/libraries/qt-5/modules/qtwebengine.nix
index cd3fa583303d..e2ca47f45f2c 100644
--- a/pkgs/development/libraries/qt-5/modules/qtwebengine.nix
+++ b/pkgs/development/libraries/qt-5/modules/qtwebengine.nix
@@ -236,6 +236,8 @@ qtModule {
     sed 's/${lib.head (lib.splitString "-" version)} /${qtCompatVersion} /' -i "$out"/lib/cmake/*/*Config.cmake
   '';
 
+  requiredSystemFeatures = [ "big-parallel" ];
+
   meta = with lib; {
     description = "A web engine based on the Chromium web browser";
     maintainers = with maintainers; [ matthewbauer ];
diff --git a/pkgs/development/libraries/webkitgtk/default.nix b/pkgs/development/libraries/webkitgtk/default.nix
index 4dbec69f8f1c..84a9e2a1db77 100644
--- a/pkgs/development/libraries/webkitgtk/default.nix
+++ b/pkgs/development/libraries/webkitgtk/default.nix
@@ -177,6 +177,8 @@ stdenv.mkDerivation rec {
     patchShebangs .
   '';
 
+  requiredSystemFeatures = [ "big-parallel" ];
+
   meta = {
     description = "Web content rendering engine, GTK port";
     homepage = "https://webkitgtk.org/";