diff --git a/bench/Main.hs b/bench/Main.hs
--- a/bench/Main.hs
+++ b/bench/Main.hs
@@ -13,7 +13,7 @@
 import           Data.Aeson
 import qualified Data.HashMap.Strict                  as HM
 import           Data.Proxy                           (Proxy (..))
-import           Data.RNG
+import           System.Random
 import qualified Data.Text                            as T
 import           Database.V1.Bloodhound.Types
 import           Numeric
@@ -24,19 +24,18 @@
 
 main :: IO ()
 main = do
-    rng <- mkRNG
     defaultMain
       [
-        mkDocIdBenchmark rng
+        mkDocIdBenchmark
       , deannotateValueBenchmark
       ]
 
 -------------------------------------------------------------------------------
-mkDocIdBenchmark :: RNG -> Benchmark
-mkDocIdBenchmark rng = bgroup "mkDocId"
+mkDocIdBenchmark :: Benchmark
+mkDocIdBenchmark = bgroup "mkDocId"
   [
     bench "mkDocId (randomIO)" $ nfIO (mkDocId (Proxy :: Proxy ESV1))
-  , bench "mkDocId' (shared )" $ nfIO $ mkDocId' rng
+  , bench "mkDocId' (shared )" $ nfIO mkDocId'
   ]
 
 
@@ -58,13 +57,11 @@
                                       ]
 
 -------------------------------------------------------------------------------
-mkDocId' :: RNG -> IO DocId
-mkDocId' rng = do
-    is <- withRNG rng $ \gen -> replicateM len $ mk gen
-    return . DocId . T.pack . concatMap (`showHex` "") $ is
+mkDocId' :: IO DocId
+mkDocId' = do
+    is <- replicateM len (randomRIO (0, 15))
+    return (DocId (T.pack (concatMap (`showHex` "") (is :: [Int]))))
   where
     len = 32
-    mk :: GenIO -> IO Int
-    mk = uniformR (0,15)
 
 deriving instance NFData DocId
diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,7 @@
+0.4.0.3
+=======
+* Fix benchmark and test builds for stackage nightly
+
 0.4.0.2
 =======
 * Add repository/homepage info to cabal file
diff --git a/katip-elasticsearch.cabal b/katip-elasticsearch.cabal
--- a/katip-elasticsearch.cabal
+++ b/katip-elasticsearch.cabal
@@ -1,7 +1,7 @@
 name:                katip-elasticsearch
 synopsis:            ElasticSearch scribe for the Katip logging framework.
 description:         See README.md for more details.
-version:             0.4.0.2
+version:             0.4.0.3
 license:             BSD3
 license-file:        LICENSE
 author:              Ozgun Ataman, Michael Xavier
@@ -72,7 +72,7 @@
                , bloodhound
                , deepseq
                , criterion >= 1.1.0.0
-               , rng-utils
+               , random
                , uuid
                , text
                , unordered-containers