diff --git a/lazyio.cabal b/lazyio.cabal
--- a/lazyio.cabal
+++ b/lazyio.cabal
@@ -1,5 +1,5 @@
 Name:             lazyio
-Version:          0.1.0.5
+Version:          0.1.0.6
 License:          BSD3
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
@@ -41,13 +41,13 @@
 Source-Repository this
   type:     darcs
   location: http://code.haskell.org/~thielema/lazyio/
-  tag:      0.1.0.5
+  tag:      0.1.0.6
 
 Library
   Build-Depends:
     unsafe >=0.0 && <0.1,
     transformers >=0.2 && <0.7,
-    base >=2 && <5
+    base >=4.8 && <5
 
   Default-Language: Haskell98
   GHC-Options:      -Wall
diff --git a/src/System/IO/Lazy.hs b/src/System/IO/Lazy.hs
--- a/src/System/IO/Lazy.hs
+++ b/src/System/IO/Lazy.hs
@@ -60,18 +60,17 @@
 data RunAll = RunAll
    deriving Show
 
-instance Monad T where
-   return x = Cons $ return x
-   x >>= f = Cons $
-      mapStateT Unsafe.interleaveIO . decons . f =<<
-      mapStateT Unsafe.interleaveIO (decons x)
-
 instance Functor T where
    fmap f = Cons . fmap f . decons
 
 instance Applicative T where
-   pure = return
+   pure = Cons . pure
    (<*>) = ap
+
+instance Monad T where
+   x >>= f = Cons $
+      mapStateT Unsafe.interleaveIO . decons . f =<<
+      mapStateT Unsafe.interleaveIO (decons x)
 
 interleave :: IO a -> T a
 interleave m = Cons $ StateT $ \RunAll -> fmap (\x->(x,RunAll)) m