diff --git a/reflex-dom-core/src/Reflex/Dom/Builder/Class.hs b/reflex-dom-core/src/Reflex/Dom/Builder/Class.hs
index 7117e827..a051c095 100644
--- a/reflex-dom-core/src/Reflex/Dom/Builder/Class.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Builder/Class.hs
@@ -22,6 +22,7 @@
 {-# LANGUAGE TemplateHaskell #-}
 #endif
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE UndecidableInstances #-}
 module Reflex.Dom.Builder.Class
        ( module Reflex.Dom.Builder.Class
diff --git a/reflex-dom-core/src/Reflex/Dom/Old.hs b/reflex-dom-core/src/Reflex/Dom/Old.hs
index aa113979..f47dc7a8 100644
--- a/reflex-dom-core/src/Reflex/Dom/Old.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Old.hs
@@ -11,6 +11,7 @@
 #ifdef USE_TEMPLATE_HASKELL
 {-# LANGUAGE TemplateHaskell #-}
 #endif
+{-# LANGUAGE TypeOperators #-}
 module Reflex.Dom.Old
        ( MonadWidget
        , El
diff --git a/reflex-dom-core/src/Reflex/Dom/Prerender.hs b/reflex-dom-core/src/Reflex/Dom/Prerender.hs
index abb93cfb..9a088332 100644
--- a/reflex-dom-core/src/Reflex/Dom/Prerender.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Prerender.hs
@@ -11,6 +11,7 @@
 {-# LANGUAGE RecursiveDo #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE UndecidableInstances #-}
 {-# LANGUAGE UndecidableSuperClasses #-}
 
diff --git a/reflex-dom-core/src/Reflex/Dom/Widget/Input.hs b/reflex-dom-core/src/Reflex/Dom/Widget/Input.hs
index 2d99d552..9f0f01e2 100644
--- a/reflex-dom-core/src/Reflex/Dom/Widget/Input.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Widget/Input.hs
@@ -13,6 +13,7 @@
 {-# LANGUAGE TemplateHaskell #-}
 #endif
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE UndecidableInstances #-}
 module Reflex.Dom.Widget.Input (module Reflex.Dom.Widget.Input, def, (&), (.~)) where
 
diff --git a/reflex-dom-core/src/Reflex/Dom/Widget/Lazy.hs b/reflex-dom-core/src/Reflex/Dom/Widget/Lazy.hs
index dd2aeecb..a944151b 100644
--- a/reflex-dom-core/src/Reflex/Dom/Widget/Lazy.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Widget/Lazy.hs
@@ -4,6 +4,7 @@
 {-# LANGUAGE RecursiveDo #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 module Reflex.Dom.Widget.Lazy where
 
 import Reflex.Class
diff --git a/reflex-dom-core/src/Reflex/Dom/Widget/Resize.hs b/reflex-dom-core/src/Reflex/Dom/Widget/Resize.hs
index f6fd95ed..84efa7af 100644
--- a/reflex-dom-core/src/Reflex/Dom/Widget/Resize.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Widget/Resize.hs
@@ -4,6 +4,7 @@
 {-# LANGUAGE RecursiveDo #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
 module Reflex.Dom.Widget.Resize where
 
 import Reflex.Class
diff --git a/reflex-dom-core/src/Reflex/Dom/Xhr.hs b/reflex-dom-core/src/Reflex/Dom/Xhr.hs
index 874938b2..31095e5a 100644
--- a/reflex-dom-core/src/Reflex/Dom/Xhr.hs
+++ b/reflex-dom-core/src/Reflex/Dom/Xhr.hs
@@ -8,6 +8,7 @@
 #ifdef USE_TEMPLATE_HASKELL
 {-# LANGUAGE TemplateHaskell #-}
 #endif
+{-# LANGUAGE TypeOperators #-}
 
 -- | A module for performing asynchronous HTTP calls from JavaScript
 -- using the