diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,30 +1,30 @@
-Copyright (c) 2013, Thomas M. DuBuisson
+Copyright (c) Thomas DuBuisson
 
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
+modification, are permitted provided that the following conditions
+are met:
 
-    * Redistributions of source code must retain the above copyright
-      notice, this list of conditions and the following disclaimer.
+1. Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
 
-    * Redistributions in binary form must reproduce the above
-      copyright notice, this list of conditions and the following
-      disclaimer in the documentation and/or other materials provided
-      with the distribution.
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
 
-    * Neither the name of Thomas M. DuBuisson nor the names of other
-      contributors may be used to endorse or promote products derived
-      from this software without specific prior written permission.
+3. Neither the name of the author nor the names of his contributors
+   may be used to endorse or promote products derived from this software
+   without specific prior written permission.
 
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND ANY EXPRESS
+OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
diff --git a/Setup.hs b/Setup.hs
--- a/Setup.hs
+++ b/Setup.hs
@@ -1,2 +1,49 @@
 import Distribution.Simple
-main = defaultMain
+import Distribution.Simple.LocalBuildInfo
+import Distribution.Simple.Setup
+import Distribution.PackageDescription
+import Distribution.Simple.Utils
+import Distribution.Simple.Program
+import Distribution.Verbosity
+import System.Process
+import System.Directory
+import System.FilePath
+import System.Exit
+
+main = defaultMainWithHooks hk
+ where
+ hk = simpleUserHooks { buildHook = \pd lbi uh bf -> do
+                                        -- let ccProg = Program "gcc" undefined undefined undefined
+                                        let hcProg = Program "ghc" undefined undefined undefined
+                                            mConf  = lookupProgram hcProg (withPrograms lbi)
+                                            err    = error "Could not determine C compiler"
+                                            cc     = locationPath . programLocation  . maybe err id $ mConf
+                                        b <- canUseRDRAND cc
+                                        let newWithPrograms1 = userSpecifyArgs "gcc" cArgs (withPrograms lbi)
+                                            newWithPrograms  = userSpecifyArgs "ghc" cArgsHC newWithPrograms1
+                                            lbiNew = if b then (lbi {withPrograms = newWithPrograms }) else lbi
+                                        buildHook simpleUserHooks pd lbiNew uh bf
+                      }
+
+cArgs :: [String]
+cArgs = ["-DHAVE_RDRAND"]
+
+cArgsHC :: [String]
+cArgsHC = map ("-optc" ++) cArgs
+
+canUseRDRAND :: FilePath -> IO Bool
+canUseRDRAND cc = do
+        withTempDirectory normal "" "testRDRAND" $ \tmpDir -> do
+        writeFile (tmpDir ++ "/testRDRAND.c")
+                (unlines        [ "#include <stdint.h>"
+                                , "int main() {"
+                                , "   uint64_t therand;"
+                                , "   unsigned char err;"
+                                , "   asm volatile(\"rdrand %0 ; setc %1\""
+                                , "     : \"=r\" (therand), \"=qm\" (err));"
+                                , "   return (!err);"
+                                , "}"
+                                ])
+        ec <- rawSystemExitCode normal cc [tmpDir </> "testRDRAND.c", "-o", tmpDir ++ "/a.o","-c"]
+        notice normal $ "Result of RDRAND Test: " ++ show (ec == ExitSuccess)
+        return (ec == ExitSuccess)
diff --git a/System/Entropy.hs b/System/Entropy.hs
--- a/System/Entropy.hs
+++ b/System/Entropy.hs
@@ -19,7 +19,6 @@
 import Control.Monad (liftM)
 import Data.ByteString as B
 import System.IO.Error (mkIOError, eofErrorType, ioeSetErrorString)
-import System.Posix (openFd, closeFd, fdReadBuf, OpenMode(..), defaultFileFlags, Fd)
 import Foreign (allocaBytes)
 
 #if defined(isWindows)
@@ -150,6 +149,7 @@
 
 #else
 {- Not windows, assuming nix with a /dev/urandom -}
+import System.Posix (openFd, closeFd, fdReadBuf, OpenMode(..), defaultFileFlags, Fd)
 import Foreign.Ptr
 
 source :: FilePath
diff --git a/entropy.cabal b/entropy.cabal
--- a/entropy.cabal
+++ b/entropy.cabal
@@ -1,5 +1,5 @@
 name:           entropy
-version:        0.2.2.3
+version:        0.2.2.4
 description:    A platform independent method to obtain cryptographically strong entropy 
                 (urandom on Linux, CryptAPI on Windows, patches welcome). 
                 Users looking for cryptographically strong (number-theoretically