diff --git a/Data/Aeson/Encode/Pretty.hs b/Data/Aeson/Encode/Pretty.hs
--- a/Data/Aeson/Encode/Pretty.hs
+++ b/Data/Aeson/Encode/Pretty.hs
@@ -34,11 +34,12 @@
              -> (Indent -> a -> Builder)
              -> [a]
              -> Builder
-fromCompound ind (delimL,delimR) fromItem items =
-    delimL <>
-    if null items then mempty
-        else "\n" <> items' <> "\n" <> fromIndent ind <>
-    delimR
+fromCompound ind (delimL,delimR) fromItem items = mconcat
+    [ delimL
+    , if null items then mempty
+        else "\n" <> items' <> "\n" <> fromIndent ind
+    , delimR
+    ]
   where
     items' = mconcat . intersperse ",\n" $
                 map (\item -> fromIndent (ind+1) <> fromItem (ind+1) item)
diff --git a/aeson-pretty.cabal b/aeson-pretty.cabal
--- a/aeson-pretty.cabal
+++ b/aeson-pretty.cabal
@@ -1,5 +1,5 @@
 name:           aeson-pretty
-version:        0.5.2
+version:        0.6
 license:        BSD3
 license-file:   LICENSE
 category:       Text, Web, JSON, Pretty Printer
@@ -42,7 +42,7 @@
         buildable: False
     else
         build-depends:
-            aeson >= 0.5 && < 0.7,
+            aeson == 0.6.*,
             attoparsec == 0.10.*,
             base == 4.*,
             bytestring == 0.9.*,
@@ -60,7 +60,7 @@
         Data.Aeson.Encode.Pretty
 
     build-depends:
-        aeson == 0.5.0.*,
+        aeson == 0.6.*,
         attoparsec == 0.10.*,
         base == 4.*,
         bytestring == 0.9.*,