diff --git a/Text/JSON.hs b/Text/JSON.hs
index 900e0f8..5b90a2a 100644
--- a/Text/JSON.hs
+++ b/Text/JSON.hs
@@ -1,4 +1,4 @@
-{-# OPTIONS_GHC -XCPP -XMultiParamTypeClasses -XTypeSynonymInstances #-}
+{-# OPTIONS_GHC -XCPP -XMultiParamTypeClasses -XTypeSynonymInstances -XFlexibleInstances #-}
 --------------------------------------------------------------------
 -- |
 -- Module    : Text.JSON