diff --git a/Control/Monad/Codec.hs b/Control/Monad/Codec.hs
--- a/Control/Monad/Codec.hs
+++ b/Control/Monad/Codec.hs
@@ -51,9 +51,10 @@
 , idLens
 ) where
 
-import Control.Applicative (Applicative, (<$>))
+import Control.Applicative (Applicative, (<$>), (<*>))
 import Data.Lens.Common (Lens, getL, setL, iso)
-import qualified Control.Monad.State as S
+import Data.Binary (Binary, put, get)
+import qualified Control.Monad.State.Strict as S
 import qualified Data.Map as M
 import qualified Data.IntMap as I
 
@@ -78,13 +79,17 @@
     { to    :: !(M.Map a Int)
     , from  :: !(I.IntMap a) }
 
+instance (Ord a, Binary a) => Binary (AtomCodec a) where
+    put atom = put (to atom) >> put (from atom)
+    get = AtomCodec <$> get <*> get
+
 -- | Empty codec component.
 empty :: AtomCodec a
 empty = AtomCodec M.empty I.empty
 
--- | Update a map with a given element and increase.  If the element
--- has not been previously in the map it will be assigned a new
--- unique integer number.
+-- | Update the map with the given element and increase the counter.  If the
+-- element has not been previously in the map it will be assigned a new unique
+-- integer number.
 updateMap :: Ord a => M.Map a Int -> a -> M.Map a Int
 updateMap mp x =
   case M.lookup x mp of
@@ -111,7 +116,8 @@
         m' = updateMap (to atomCodec) x
         y  = m' M.! x
         r' = I.insert y x (from atomCodec)
-        codec' = setL lens (AtomCodec m' r') codec
+        !atom = AtomCodec m' r'
+        codec' = setL lens atom codec
     setCodec codec'
     return y
 
@@ -125,7 +131,8 @@
     let atomCodec = getL lens codec
         m' = updateMap (to atomCodec) x
         y  = m' M.! x
-        codec' = setL lens (atomCodec { to = m' }) codec
+        !atom = atomCodec { to = m' }
+        codec' = setL lens atom  codec
     setCodec codec'
     return y
 
diff --git a/monad-codec.cabal b/monad-codec.cabal
--- a/monad-codec.cabal
+++ b/monad-codec.cabal
@@ -1,5 +1,5 @@
 name:               monad-codec
-version:            0.1.1
+version:            0.2.0
 synopsis:           Monadic conversion between complex data structures and unique integers
 description:
     The library provides functions for encoding and decoding complex data
@@ -23,6 +23,7 @@
       , containers
       , data-lens
       , mtl >= 2
+      , binary
 
     exposed-modules:
         Control.Monad.Codec