diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,165 @@
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
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diff --git a/README b/README
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--- /dev/null
+++ b/README
@@ -0,0 +1,1 @@
+There's a wiki: http://patch-tag.com/r/shahn/clocked/wiki/
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,5 @@
+#!/usr/bin/runhaskell
+
+import Distribution.Simple
+
+main = defaultMain
diff --git a/clocked.cabal b/clocked.cabal
new file mode 100644
--- /dev/null
+++ b/clocked.cabal
@@ -0,0 +1,59 @@
+Name:                clocked
+Version:             0.4.1
+Synopsis:            timer functionality to clock IO commands
+Description:         clocked is a library that allows you to clock IO-operations. You can use it to clock the rendering of frames, the calculation of steps in a physics engine, the triggering of musical events in a real-time system, etc.
+Homepage:            http://patch-tag.com/r/shahn/clocked/home
+License:             LGPL-3
+License-file:        LICENSE
+Author:              Sönke Hahn
+Maintainer:          shahn@joyridelabs.de
+Category:            Concurrency
+Build-type:          Simple
+
+Cabal-version:       >=1.8
+
+extra-source-files:
+    README
+
+source-repository head
+  type:     darcs
+  location: http://patch-tag.com/r/shahn/clocked
+
+Library
+    exposed-modules:
+        Clocked
+    other-modules:
+        Clocked.Common,
+        Clocked.WinTimePeriod
+
+    ghc-options:
+        -O3
+
+    hs-source-dirs:
+        -- choosing qt backend
+        src, src/qt-heuristic-seq
+    c-sources:
+        src/qt-heuristic-seq/clocked.cpp
+    if os(mingw32)
+        c-sources:
+            src/Clocked/WinTimePeriod.c
+    build-depends:
+        base >= 4 && < 5,
+        transformers,
+        MonadCatchIO-transformers,
+        containers
+    if !os(darwin)
+        build-depends:
+            clock
+
+    extra-libraries:
+        stdc++
+    if os(linux)
+        PkgConfig-Depends:
+            QtCore
+    if os(mingw32)
+        extra-libraries:
+            QtCore4
+    if os(darwin)
+        frameworks:
+            QtCore
diff --git a/src/Clocked/Common.hs b/src/Clocked/Common.hs
new file mode 100644
--- /dev/null
+++ b/src/Clocked/Common.hs
@@ -0,0 +1,32 @@
+{-# language CPP #-}
+
+module Clocked.Common where
+
+
+#ifdef darwin_HOST_OS
+
+
+import Control.Applicative ((<$>))
+
+import Data.Time.Clock.POSIX
+
+getTimeDouble = realToFrac <$> getPOSIXTime
+
+
+#else
+
+
+import Control.Applicative ((<$>))
+
+import System.Posix.Clock
+
+-- | returns a monotonic time in seconds
+getTimeDouble :: IO Double
+getTimeDouble =
+    toSeconds <$> getTime Monotonic
+  where
+    toSeconds (TimeSpec seconds nanoSeconds) =
+        fromIntegral seconds + fromIntegral nanoSeconds * 10 ** (- 9)
+
+
+#endif
diff --git a/src/Clocked/WinTimePeriod.c b/src/Clocked/WinTimePeriod.c
new file mode 100644
--- /dev/null
+++ b/src/Clocked/WinTimePeriod.c
@@ -0,0 +1,11 @@
+
+#include "windows.h"
+
+
+void c_timeBeginPeriod(unsigned int uPeriod) {
+    timeBeginPeriod(uPeriod);
+};
+
+void c_timeEndPeriod(unsigned int uPeriod) {
+    timeEndPeriod(uPeriod);
+};
diff --git a/src/Clocked/WinTimePeriod.hs b/src/Clocked/WinTimePeriod.hs
new file mode 100644
--- /dev/null
+++ b/src/Clocked/WinTimePeriod.hs
@@ -0,0 +1,32 @@
+{-# language CPP, ForeignFunctionInterface #-}
+
+module Clocked.WinTimePeriod (withTimePeriod) where
+
+#ifdef mingw32_HOST_OS
+
+
+import Control.Monad.CatchIO
+import Control.Monad.IO.Class
+
+import Foreign.C.Types
+
+foreign import ccall c_timeBeginPeriod :: CUInt -> IO ()
+foreign import ccall c_timeEndPeriod :: CUInt -> IO ()
+
+withTimePeriod :: MonadCatchIO m => CUInt -> m a -> m a
+withTimePeriod n cmd =
+    bracket (liftIO $ c_timeBeginPeriod n) (const $ liftIO $ c_timeEndPeriod n) (const $ cmd)
+
+    
+#else
+
+
+import Control.Monad.CatchIO
+
+import Foreign.C.Types
+
+withTimePeriod :: MonadCatchIO m => CUInt -> m a -> m a
+withTimePeriod _ = id
+
+
+#endif
diff --git a/src/qt-heuristic-seq/Clocked.hs b/src/qt-heuristic-seq/Clocked.hs
new file mode 100644
--- /dev/null
+++ b/src/qt-heuristic-seq/Clocked.hs
@@ -0,0 +1,91 @@
+
+{-# language ForeignFunctionInterface, ScopedTypeVariables #-}
+
+-- Implementation using qt
+-- and a heuristic to shorten the time span to be waited
+-- to get closer to the wanted time span.
+
+module Clocked (
+    Timer,
+    withTimer,
+    waitTimer,
+    getTimeDouble,
+  ) where
+
+
+import Data.IORef
+import Data.Sequence
+
+import Control.Monad
+import Control.Monad.CatchIO
+import Control.Monad.IO.Class
+import Control.Applicative ((<$>))
+
+import Clocked.Common
+import Clocked.WinTimePeriod
+
+
+-- | The heuristic correction is calculated using a moving average
+-- of the time deviation. This is the size of the window for
+-- calculating the moving average.
+windowSize :: Double
+windowSize = 10
+
+-- | Estimate of the time deviation.
+-- Empiric data on linux (2.6.35-28)
+initialDeviation = 0.00018
+
+-- | the heuristic correction gets limited by a fraction of the wanted time span
+heuristicCorrectionFraction = 0.1
+
+foreign import ccall qtUSleep :: Int -> IO ()
+
+newtype Timer = Timer (IORef State)
+
+-- | Run a monadic action with a 'Timer'.
+withTimer :: MonadCatchIO m => (Timer -> m a) -> m a
+withTimer m = withTimePeriod 1 $
+    (m =<< liftIO (Timer <$> (newIORef =<< mkState)))
+
+data State = State {
+    lastTime :: Double,
+    deviations :: Seq Double,
+    deviationMovingAverage :: Double
+  }
+
+mkState :: IO State
+mkState = do
+    now <- getTimeDouble
+    return $ State now (mkFullBuffer (round windowSize) initialDeviation) initialDeviation
+
+-- | Waits the given amount of seconds minus the elapsed time
+-- since the last call to 'waitTimer' (or the initialisation of the timer).
+waitTimer :: Timer -> Double -> IO ()
+waitTimer (Timer ref) waitSeconds = do
+    state <- readIORef ref
+    now <- getTimeDouble
+    let heuristicCorrection = deviationMovingAverage state
+        waitTime :: Double = waitSeconds - (now - lastTime state) - heuristicCorrection
+        waitMicroSeconds = round (waitTime * 10 ^ 6)
+    when (waitMicroSeconds > 0) $
+        qtUSleep waitMicroSeconds
+    after <- getTimeDouble
+    let actuallyWaited = after - lastTime state
+        deviation = min
+            (actuallyWaited - waitSeconds + heuristicCorrection)
+            (waitSeconds * heuristicCorrectionFraction)
+        (droppedDeviation, newBuffer) = crank deviation (deviations state)
+        newAverage = deviationMovingAverage state + ((deviation - droppedDeviation) / windowSize)
+        state' = State after newBuffer newAverage
+    writeIORef ref state'
+
+
+-- * buffer functions for Seq
+
+mkFullBuffer :: Int -> a -> Seq a
+mkFullBuffer = Data.Sequence.replicate
+
+crank :: a -> Seq a -> (a, Seq a)
+crank new buffer = case viewl buffer of
+    head :< tail -> (head, tail |> new)
+    EmptyL -> error "crank on empty buffer"
diff --git a/src/qt-heuristic-seq/clocked.cpp b/src/qt-heuristic-seq/clocked.cpp
new file mode 100644
--- /dev/null
+++ b/src/qt-heuristic-seq/clocked.cpp
@@ -0,0 +1,22 @@
+
+
+#include <QtCore/QThread>
+#include <QtCore/QtDebug>
+
+
+class MyThread : public QThread {
+
+public:
+    void myUSleep(int microSeconds);
+
+};
+
+void MyThread::myUSleep(int microSeconds) {
+    QThread::usleep(microSeconds);
+};
+
+MyThread* myThread = new MyThread();
+
+extern "C" void qtUSleep(int microSeconds) {
+    myThread->myUSleep(microSeconds);
+};