diff --git a/delta.cabal b/delta.cabal
--- a/delta.cabal
+++ b/delta.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.1.0.1
+version:             0.1.2.0
 
 -- A short (one-line) description of the package.
 synopsis:            A library for detecting file changes
@@ -51,7 +51,7 @@
 -- extra-source-files:  
 
 -- Constraint on the version of Cabal needed to build this package.
-cabal-version:       >=1.16
+cabal-version:       >= 1.18
 
 source-repository head
   type:              git
@@ -77,7 +77,6 @@
                      , filepath >= 1.3
                      , time >= 1.5
                      , sodium >= 0.11
-                     , fs-events
   
   -- Directories containing source files.
   hs-source-dirs:      src
@@ -87,12 +86,7 @@
 
 executable delta-cli
 
-  build-depends:       base >= 4.8 && < 4.9
-                     , containers >= 0.5
-                     , directory >= 1.2
-                     , filepath >= 1.3
-                     , time >= 1.5
-                     , sodium >= 0.11
+  build-depends:       base >= 4.6 && < 4.9
                      , delta
 
   hs-source-dirs:      src/delta-cli
diff --git a/src/System/Delta.hs b/src/System/Delta.hs
--- a/src/System/Delta.hs
+++ b/src/System/Delta.hs
@@ -1,10 +1,56 @@
 {-# LANGUAGE RankNTypes #-}
+--------------------------------------------------------------------------------
+-- |
+-- Module : System.Delta
+-- Copyright: (c) Christof Schramm 2015
+-- License: LGPL v2
+--
+-- Maintainer: Christof Schramm
+-- Stability: Experimental
+--
+-- = Description
+--
+-- An umberella package for the delta library. This library can be used to monitor
+-- changed / new / deleted files in a given directory (or set of directories).
+--
+-- Currently this library polls the directories of interest recursively in certain
+-- intervals, but I will add OS-specific functionality to monitor the filesystem.
+--
+-- = Examples
+--
+-- Create a watcher that prints a line if a new file is created in the monitored
+-- directory:
+--
+-- @
+-- printNewFilePaths basePath = do
+--   watcher <- deltaDirWithCallbacks basePath
+--   withNewCallback watcher (\\x -> putStrLn $ "new file: " ++ x)
+-- @
+--------------------------------------------------------------------------------
 module System.Delta ( module System.Delta.Base
                     , module System.Delta.Poll
-                    , module System.Delta.Class
-                    , module System.Delta.Callback
+
+                    -- * Important functions
                     , deltaDir
                     , deltaDirWithCallbacks
+
+                    -- * FRP based interface
+                    , module System.Delta.Class
+                    , FileWatcher(..)
+
+                    -- * Callback based interface
+                    , module System.Delta.Callback
+                    , CallbackWatcher
+                    , CallbackId
+                    , withCallbacks
+                    -- ** Adding callbacks
+                    , withDeleteCallback
+                    , withChangedCallback
+                    , withNewCallback
+                    -- ** Removing callbacks
+                    , unregisterCallback
+                    , removeAllCallbacks
+                    , closeCallbackWatcher
                     )where
 
 import System.Delta.Base
@@ -12,7 +58,7 @@
 import System.Delta.Class
 import System.Delta.Callback
 
--- | Build a file watcher
+-- | Build a file watcher, this method will change later
 deltaDir :: FilePath -> IO PollWatcher
 deltaDir path = defaultWatcher path
 
diff --git a/src/System/Delta/Callback.hs b/src/System/Delta/Callback.hs
--- a/src/System/Delta/Callback.hs
+++ b/src/System/Delta/Callback.hs
@@ -26,9 +26,11 @@
 
 import Control.Concurrent.MVar
 
+-- | Id of a callback in a 'CallbackWatcher'
 newtype CallbackId = CallbackId Integer
                    deriving (Eq, Ord)  
 
+-- | Provides a callback based interface to an FRP base 'FileWatcher'
 data CallbackWatcher w where
   CallbackWatcher :: FileWatcher w => {
     baseWatcher :: w
diff --git a/src/System/Delta/Class.hs b/src/System/Delta/Class.hs
--- a/src/System/Delta/Class.hs
+++ b/src/System/Delta/Class.hs
@@ -3,6 +3,16 @@
 import FRP.Sodium
 import System.Delta.Base
 
+import Control.Monad
+
+-- | A class for watching a directory based on functional reactive programming
+-- At the core of this class are three event streams:
+--
+-- * @changedFiles@ is a stream of 'FileInfo's on changed files
+--
+-- * @newFiles@ is a stream of canonicalized 'FilePath's of newly created files
+--
+-- * @deletedFiles@ is a stream of canonicalized 'FilePath's of deleted files
 class FileWatcher a where
   -- | Each type provides a default watcher for a pass
   defaultWatcher  :: FilePath -> IO a
@@ -21,3 +31,13 @@
   -- this.
   cleanUpAndClose :: a -> IO ()
 
+  -- | Merge two watchers that are watching different directories
+  mergeWatchers :: a -> a -> a
+
+  -- | Create a watcher on all of the given paths
+  watchPaths :: (FileWatcher a) => [FilePath] -> Maybe (IO a)
+  watchPaths []    = Nothing
+  watchPaths paths = Just $ do
+    watchers <- mapM defaultWatcher paths
+    let combinedWatcher = foldl1 mergeWatchers watchers
+    return $ combinedWatcher
diff --git a/src/System/Delta/Poll.hs b/src/System/Delta/Poll.hs
--- a/src/System/Delta/Poll.hs
+++ b/src/System/Delta/Poll.hs
@@ -17,19 +17,29 @@
 import System.Directory
 import System.FilePath
 
+import Data.List (isPrefixOf)
+
 data PollWatcher = PollWatcher
-                     FilePath
+                     [FilePath]
                      (Event FileInfo)
                      (Event FilePath)
                      (Event FilePath)
-                     ThreadId
+                     [ThreadId]
 
 instance FileWatcher PollWatcher where
   defaultWatcher = createPollWatcher 3
   changedFiles (PollWatcher _ e _ _ _) = e
   newFiles     (PollWatcher _ _ e _ _) = e
   deletedFiles (PollWatcher _ _ _ e _) = e
-  cleanUpAndClose (PollWatcher _ _ _ _ tId) = killThread tId
+  cleanUpAndClose (PollWatcher _ _ _ _ tIds) = mapM_ killThread tIds
+  mergeWatchers (PollWatcher pA cA nA dA idsA) (PollWatcher pB cB nB dB idsB) =
+    PollWatcher
+      (pA ++ pB)
+      (merge cA cB)
+      (merge nA nB)
+      (merge dA dB)
+      (idsA ++ idsB)
+    
 
 -- | Watch files in this directory recursively for changes every
 -- n seconds.
@@ -40,8 +50,9 @@
   (changedEvent, pushChanged) <- sync $ newEvent
   (deletedEvent, pushDeleted) <- sync $ newEvent
   (newFileEvent, pushNewFile) <- sync $ newEvent
-  watcherId <- startWatchThread path pushNewFile pushDeleted pushChanged secs
-  return $ PollWatcher path changedEvent newFileEvent deletedEvent watcherId
+  canonPath <- canonicalizePath path
+  watcherId <- startWatchThread canonPath pushNewFile pushDeleted pushChanged secs
+  return $ PollWatcher [canonPath] changedEvent newFileEvent deletedEvent [watcherId]
 
 -- | Recursively traverse a folder, follow symbolic links but don't
 -- visit a file twice.