diff --git a/src/Graphics/Vty/UnicodeWidthTable/IO.hs b/src/Graphics/Vty/UnicodeWidthTable/IO.hs
index 84d70d4..e0a5e04 100644
--- a/src/Graphics/Vty/UnicodeWidthTable/IO.hs
+++ b/src/Graphics/Vty/UnicodeWidthTable/IO.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 module Graphics.Vty.UnicodeWidthTable.IO
   ( readUnicodeWidthTable
   , writeUnicodeWidthTable
@@ -9,6 +10,9 @@ import Data.Binary
 import Data.Binary.Get
 import Data.Binary.Put
 import qualified Data.ByteString.Lazy as BSL
+#if !(MIN_VERSION_base(4,11,0))
+import Data.Semigroup ((<>))
+#endif
 
 import Graphics.Vty.UnicodeWidthTable.Types
 
diff --git a/src/Graphics/Vty/UnicodeWidthTable/Install.hs b/src/Graphics/Vty/UnicodeWidthTable/Install.hs
index 5d96c02..ae04372 100644
--- a/src/Graphics/Vty/UnicodeWidthTable/Install.hs
+++ b/src/Graphics/Vty/UnicodeWidthTable/Install.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE ForeignFunctionInterface #-}
 module Graphics.Vty.UnicodeWidthTable.Install
   ( installUnicodeWidthTable
@@ -8,6 +9,9 @@ where
 
 import Control.Monad (when, forM_)
 import Data.Word (Word8, Word32)
+#if !(MIN_VERSION_base(4,11,0))
+import Data.Semigroup ((<>))
+#endif
 
 import Graphics.Vty.UnicodeWidthTable.Types