diff --git a/yesod-test/Yesod/Test/Internal.hs b/yesod-test/Yesod/Test/Internal.hs
index b035b5f0..c4057f52 100644
--- a/yesod-test/Yesod/Test/Internal.hs
+++ b/yesod-test/Yesod/Test/Internal.hs
@@ -18,6 +18,7 @@ import qualified Data.Text.Encoding as TE
 import qualified Data.Text.Lazy as TL
 import qualified Data.Text.Lazy.Encoding as DTLE
 import qualified Yesod.Core.Content as Content
+import Data.Semigroup (Semigroup(..))
 
 -- | Helper function to get the first 1024 characters of the body, assuming it is UTF-8.
 -- This function is used to preview the body in case of an assertion failure.