diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2014 HirotomoMoriwaki
+Copyright (c) 2014-2015 HirotomoMoriwaki
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
diff --git a/helics.cabal b/helics.cabal
--- a/helics.cabal
+++ b/helics.cabal
@@ -1,5 +1,5 @@
 name:                helics
-version:             0.5.0.1
+version:             0.5.1
 synopsis:            New Relic® agent SDK wrapper for Haskell.
 description:         
   New Relic® agent SDK wrapper for Haskell.
@@ -19,7 +19,7 @@
 maintainer:          HirotomoMoriwaki<philopon.dependence@gmail.com>
 Homepage:            https://github.com/philopon/helics
 Bug-reports:         https://github.com/philopon/helics/issues
-copyright:           (c) 2014 Hirotomo Moriwaki
+copyright:           (c) 2014-2015 Hirotomo Moriwaki
 category:            Network
 stability:           experimental
 build-type:          Custom
@@ -42,7 +42,7 @@
                        Network.Helics.Internal.Types
   ghc-options:         -Wall -O2
   default-language:    Haskell2010
-  build-depends:       base               >=4.6  && <4.8
+  build-depends:       base               >=4.6  && <4.9
                      , data-default-class >=0.0  && <0.1
                      , bytestring         >=0.10 && <0.11
 
diff --git a/src/Network/Helics/Sampler.hs b/src/Network/Helics/Sampler.hs
--- a/src/Network/Helics/Sampler.hs
+++ b/src/Network/Helics/Sampler.hs
@@ -6,8 +6,6 @@
 
 import GHC.Conc
 
-import Control.Applicative
-
 import Network.Helics.Foreign.System
 
 import Data.Time.Clock
@@ -16,24 +14,24 @@
 
 sampler :: Callback -> Int -> IO ()
 sampler callback sleep = do
-    t     <- fromIntegral <$> clockTick
-    core  <- fromIntegral <$> getNumCapabilities
+    t     <- fromIntegral `fmap` clockTick
+    core  <- fromIntegral `fmap` getNumCapabilities
     cTime <- getCurrentTime
-    uTime <- fromIntegral <$> getUserTime
-    pSize <- fromIntegral <$> pageSize
+    uTime <- fromIntegral `fmap` getUserTime
+    pSize <- fromIntegral `fmap` pageSize
     pid   <- getProcessID
     threadDelay sleep
     go t core pSize pid cTime uTime
   where
 
     unCClock (CClock c) = c
-    getUserTime = unCClock . userTime <$> getProcessTimes
+    getUserTime = (unCClock . userTime) `fmap` getProcessTimes
 
     go tick core pSize pid = loop
       where
         loop cTime uTime = do
             cTime' <- getCurrentTime
-            uTime' <- fromIntegral <$> getUserTime
+            uTime' <- fromIntegral `fmap` getUserTime
             pages  <- getPages pid
             let real = realToFrac $ diffUTCTime cTime' cTime
                 user = (uTime' - uTime) / tick