diff --git a/Network/HTTP/Date/Parser.hs b/Network/HTTP/Date/Parser.hs
--- a/Network/HTTP/Date/Parser.hs
+++ b/Network/HTTP/Date/Parser.hs
@@ -3,6 +3,7 @@
 module Network.HTTP.Date.Parser (parseHTTPDate) where
 
 import Control.Applicative
+import Control.Monad
 import Data.Attoparsec
 import Data.Attoparsec.Char8
 import Data.ByteString
@@ -25,12 +26,12 @@
 rfc1123Date :: Parser HTTPDate
 rfc1123Date = do
     w <- wkday
-    string ", "
+    void $ string ", "
     (y,m,d) <- date1
     sp
     (h,n,s) <- time
     sp
-    string "GMT"
+    void $ string "GMT"
     return $ defaultHTTPDate {
         hdYear   = y
       , hdMonth  = m
@@ -68,9 +69,9 @@
 time :: Parser (Int,Int,Int)
 time = do
     h <- digit2
-    char ':'
+    void $ char ':'
     m <- digit2
-    char ':'
+    void $ char ':'
     s <- digit2
     return (h,m,s)
 
diff --git a/http-date.cabal b/http-date.cabal
--- a/http-date.cabal
+++ b/http-date.cabal
@@ -1,5 +1,5 @@
 Name:                   http-date
-Version:                0.0.2
+Version:                0.0.3
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3
@@ -11,10 +11,7 @@
 Build-Type:             Simple
 
 Library
-  if impl(ghc >= 6.12)
-    GHC-Options:        -Wall -fno-warn-unused-do-bind
-  else
-    GHC-Options:        -Wall
+  GHC-Options:          -Wall
   Exposed-Modules:      Network.HTTP.Date
   Other-Modules:        Network.HTTP.Date.Converter
                         Network.HTTP.Date.Formatter
@@ -25,21 +22,27 @@
                       , attoparsec
                       , bytestring
 
-Test-Suite test
+Test-Suite spec
   Type:                 exitcode-stdio-1.0
   HS-Source-Dirs:       test
-  Main-Is:              Test.hs
-  Other-Modules:        Model
+  Main-Is:              Spec.hs
+  Other-Modules:        DateSpec
+                        Model
   Build-Depends:        base >= 4 && < 5
                       , bytestring
+                      , hspec
                       , http-date
                       , old-locale
                       , time
-                      , HUnit
-                      , test-framework-doctest
-                      , test-framework-hunit
-                      , test-framework-th-prime
 
+Test-Suite doctests
+  Type:                 exitcode-stdio-1.0
+  HS-Source-Dirs:       test
+  Ghc-Options:          -threaded
+  Main-Is:              doctests.hs
+  Build-Depends:        base
+                      , doctest >= 0.8
+
 Source-Repository head
   Type:                 git
-  Location:             git clone git://github.com/kazu-yamamoto/http-date
+  Location:             git://github.com/kazu-yamamoto/http-date
diff --git a/test/DateSpec.hs b/test/DateSpec.hs
new file mode 100644
--- /dev/null
+++ b/test/DateSpec.hs
@@ -0,0 +1,25 @@
+module DateSpec where
+
+import Control.Monad
+import Model
+import Network.HTTP.Date
+import Test.Hspec
+
+----------------------------------------------------------------
+
+spec :: Spec
+spec = do
+    describe "formatHTTPDat" $ do
+        it "behaves like the model" $ 
+            forM_ [0,100000..10000000000] $ \epochtime -> do
+                let m = model epochtime
+                    o = ours epochtime
+                    model = utcToDate . epochTimeToUtcTime
+                    ours  = formatHTTPDate . epochTimeToHTTPDate
+                o `shouldBe` m
+    describe "parseHTTPDate" $ do
+        it "behaves like the model" $ 
+            forM_ [0,100000..10000000000] $ \epochtime -> do
+                let m = epochTimeToHTTPDate epochtime
+                    Just o = parseHTTPDate $ formatHTTPDate m
+                o `shouldBe` m
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}
diff --git a/test/Test.hs b/test/Test.hs
deleted file mode 100644
--- a/test/Test.hs
+++ /dev/null
@@ -1,38 +0,0 @@
-{-# LANGUAGE TemplateHaskell #-}
-
-module Main where
-
-import Control.Monad
-import Model
-import Network.HTTP.Date
-import Test.Framework.Providers.DocTest
-import Test.Framework.Providers.HUnit
-import Test.Framework.TH.Prime
-import Test.HUnit
-
-main :: IO ()
-main = $(defaultMainGenerator)
-
-----------------------------------------------------------------
-
-doc_test :: DocTests
-doc_test = docTest ["Network/HTTP/Date"] ["-XOverloadedStrings"]
-
-----------------------------------------------------------------
-
-case_formatHTTPDate :: Assertion
-case_formatHTTPDate = do
-    forM_ [0,100000..10000000000] $ \epochtime -> do
-        let m = model epochtime
-            o = ours epochtime
-        o @?= m
-  where
-    model = utcToDate . epochTimeToUtcTime
-    ours  = formatHTTPDate . epochTimeToHTTPDate
-
-case_parseHTTPDate :: Assertion
-case_parseHTTPDate = do
-    forM_ [0,100000..10000000000] $ \epochtime -> do
-        let m = epochTimeToHTTPDate epochtime
-            Just o = parseHTTPDate $ formatHTTPDate m
-        o @?= m
diff --git a/test/doctests.hs b/test/doctests.hs
new file mode 100644
--- /dev/null
+++ b/test/doctests.hs
@@ -0,0 +1,6 @@
+module Main where
+
+import Test.DocTest
+
+main :: IO ()
+main = doctest ["-XOverloadedStrings", "Network/HTTP/Date.hs"]