diff --git a/MemoTrie.cabal b/MemoTrie.cabal
--- a/MemoTrie.cabal
+++ b/MemoTrie.cabal
@@ -1,5 +1,5 @@
 Name:                MemoTrie
-Version:             0.6.5
+Version:             0.6.6
 Cabal-Version:       >= 1.10
 Synopsis:            Trie-based memo functions
 Category:            Data
@@ -33,10 +33,9 @@
   hs-Source-Dirs:      src
 
   if impl(ghc >= 7.10.0)
-     Build-Depends: base >=4.8.0.0 && <5
-                  , newtype-generics >= 0.4
+     Build-Depends: base >=4.8.0.0 && <5, newtype-generics >= 0.4
   else
-     Build-Depends: base <4.8.0.0, void
+     Build-Depends: base <4.8.0.0, void, newtype-generics >= 0.4
 
   Exposed-Modules:     
                      Data.MemoTrie
diff --git a/src/Data/MemoTrie.hs b/src/Data/MemoTrie.hs
--- a/src/Data/MemoTrie.hs
+++ b/src/Data/MemoTrie.hs
@@ -64,9 +64,13 @@
 import Data.Bits
 import Data.Word
 import Data.Int
--- import Control.Applicative
+#if !MIN_VERSION_base(4,8,0)
+import Control.Applicative
+#endif
 import Control.Arrow (first,(&&&))
--- import Data.Monoid
+#if !MIN_VERSION_base(4,8,0)
+import Data.Monoid
+#endif
 import Data.Function (on)
 import GHC.Generics