diff --git a/Network/Kafka.hs b/Network/Kafka.hs
--- a/Network/Kafka.hs
+++ b/Network/Kafka.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE FlexibleContexts #-}
 
 module Network.Kafka where
 
diff --git a/Network/Kafka/Producer.hs b/Network/Kafka/Producer.hs
--- a/Network/Kafka/Producer.hs
+++ b/Network/Kafka/Producer.hs
@@ -1,10 +1,13 @@
 module Network.Kafka.Producer where
 
+import Prelude hiding ((!!))
 import Control.Applicative
 import Control.Lens
 import Control.Monad.Trans (liftIO, lift)
 import Control.Monad.Trans.Either
 import Data.ByteString.Char8 (ByteString)
+import qualified Data.Digest.Murmur32 as Murmur32
+import Data.List.Safe ((!!))
 import Data.Monoid ((<>))
 import System.IO
 import qualified Data.Map as M
@@ -43,13 +46,22 @@
       where recurse [] accum = return accum
             recurse (x:xs) accum = do
               topicPartitionsList <- brokerPartitionInfo $ _tamTopic x
-              pal <- getPartition topicPartitionsList
+              let maybeKey = x ^. tamMessage . messageKey . keyBytes
+              pal <- case maybeKey of
+                Nothing -> getRandPartition topicPartitionsList
+                Just key -> return $ getPartitionByKey (_kafkaByteString key) topicPartitionsList
               let leader = maybe (Leader Nothing) _palLeader pal
                   tp = TopicAndPartition <$> pal ^? folded . palTopic <*> pal ^? folded . palPartition
                   b = M.singleton leader $ maybe M.empty (`M.singleton` [x]) tp
                   accum' = M.unionWith (M.unionWith (<>)) accum b
               recurse xs accum'
 
+-- | Compute the partition for a record. This matches the way the official
+-- | clients compute the partition.
+getPartitionByKey :: ByteString -> [PartitionAndLeader] -> Maybe PartitionAndLeader
+getPartitionByKey key ps = let i = Murmur32.asWord32 $ Murmur32.hash32WithSeed 0x9747b28c key
+                           in ps !! i
+
 -- | Execute a produce request using the values in the state.
 send :: Leader -> [(TopicAndPartition, MessageSet)] -> Kafka ProduceResponse
 send l ts = do
@@ -80,8 +92,8 @@
         Just x -> return x
         Nothing -> lift $ left $ err
 
-getPartition :: [PartitionAndLeader] -> Kafka (Maybe PartitionAndLeader)
-getPartition ps =
+getRandPartition :: [PartitionAndLeader] -> Kafka (Maybe PartitionAndLeader)
+getRandPartition ps =
     liftIO $ (ps' ^?) . element <$> getStdRandom (randomR (0, length ps' - 1))
         where ps' = ps ^.. folded . filtered (has $ palLeader . leaderId . _Just)
 
diff --git a/Network/Kafka/Protocol.hs b/Network/Kafka/Protocol.hs
--- a/Network/Kafka/Protocol.hs
+++ b/Network/Kafka/Protocol.hs
@@ -491,6 +491,12 @@
 fetchResponseMessageMembers :: Fold FetchResponse MessageSetMember
 fetchResponseMessageMembers = fetchResponseMessages . messageSetMembers . folded
 
+messageKey :: Lens' Message Key
+messageKey = messageFields . _4
+
+messageKeyBytes :: Fold Message ByteString
+messageKeyBytes = messageKey . keyBytes . folded . kafkaByteString
+
 messageValue :: Lens' Message Value
 messageValue = messageFields . _5
 
diff --git a/milena.cabal b/milena.cabal
--- a/milena.cabal
+++ b/milena.cabal
@@ -4,9 +4,10 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.2.0.0
+version:             0.3.0.0
 synopsis:            A Kafka client for Haskell.
-description:         Kafka client for Haskell (not recommended for production use).
+description:
+    The protocol module is stable (the only changes will be to support changes in the Kafka protocol). The API is functional but subject to change.
 license:             BSD3
 license-file:        LICENSE
 author:              Tyler Holien
@@ -24,7 +25,7 @@
 source-repository this
   type: git
   location: https://github.com/tylerholien/milena.git
-  tag: 0.2.0.0
+  tag: 0.3.0.0
 
 library
   default-language: Haskell2010
@@ -42,14 +43,18 @@
                        either        >=4.3      && <4.4,
                        random        >=1.0      && <1.2,
                        transformers  >=0.3      && <0.5,
-                       lens          >=4.4      && <4.8,
-                       resource-pool >=0.2.3.2  && <0.3
+                       lens          >=4.4      && <4.13,
+                       resource-pool >=0.2.3.2  && <0.3,
+                       lifted-base   >=0.2.3.6  && <0.3,
+                       murmur-hash   >=0.1.0.8  && <0.2,
+                       listsafe      >=0.1.0.1  && <0.2
 
 test-suite test
   default-language: Haskell2010
   ghc-options:         -Wall -threaded
   build-depends:       base,
                        milena,
+                       mtl,
                        network,
                        QuickCheck,
                        bytestring,
diff --git a/test/tests.hs b/test/tests.hs
--- a/test/tests.hs
+++ b/test/tests.hs
@@ -14,7 +14,7 @@
 main :: IO ()
 main = hspec $ do
   let topic = "milena-test"
-      run = runKafka ("kafka1.dev", 9093) $ defaultState "milena-test-client"
+      run = runKafka ("localhost", 9092) $ defaultState "milena-test-client"
       byteMessages = fmap (TopicAndMessage topic . makeMessage . B.pack)
 
   describe "can talk to local Kafka server" $ do
@@ -32,7 +32,7 @@
       let messages = byteMessages ms
       result <- run $ do
         info <- brokerPartitionInfo topic
-        leader <- maybe (Leader Nothing) _palLeader <$> getPartition info
+        leader <- maybe (Leader Nothing) _palLeader <$> getRandPartition info
         offset <- getLastOffset LatestTime 0 topic
         void $ send leader [(TopicAndPartition topic 0, groupMessagesToSet messages)]
         fmap tamPayload . fetchMessages <$> (fetch =<< fetchRequest offset 0 topic)