diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+1.4.12
+
+* `Data.Functor.Extend.Extended` instances for `Fold` / `FoldM`
+* Remove dependency on `mwc-random`
+
 1.4.11
 
 * Fix doctest failure when built against newer versions of the `hashable`
diff --git a/foldl.cabal b/foldl.cabal
--- a/foldl.cabal
+++ b/foldl.cabal
@@ -1,5 +1,5 @@
 Name: foldl
-Version: 1.4.11
+Version: 1.4.12
 Cabal-Version: >=1.10
 Build-Type: Simple
 License: BSD3
@@ -26,7 +26,7 @@
     Build-Depends:
         base         >= 4.8      && < 5   ,
         bytestring   >= 0.9.2.1  && < 0.12,
-        mwc-random   >= 0.13.1.0 && < 0.16,
+        random       >= 1.2      && < 1.3 ,
         primitive                   < 0.8 ,
         text         >= 0.11.2.0 && < 1.3 ,
         transformers >= 0.2.0.0  && < 0.6 ,
diff --git a/src/Control/Foldl.hs b/src/Control/Foldl.hs
--- a/src/Control/Foldl.hs
+++ b/src/Control/Foldl.hs
@@ -160,6 +160,7 @@
 import Data.Monoid hiding ((<>))
 import Data.Semigroup (Semigroup(..))
 import Data.Semigroupoid (Semigroupoid)
+import Data.Functor.Extend (Extend(..))
 import Data.Profunctor
 import Data.Sequence ((|>))
 import Data.Vector.Generic (Vector, Mutable)
@@ -167,7 +168,7 @@
 import Data.Hashable (Hashable)
 import Data.Traversable
 import Numeric.Natural (Natural)
-import System.Random.MWC (GenIO, createSystemRandom, uniformR)
+import System.Random (StdGen, newStdGen, uniformR)
 import Prelude hiding
     ( head
     , last
@@ -260,6 +261,10 @@
         in  Fold step begin done
     {-# INLINE (<*>) #-}
 
+instance Extend (Fold a) where
+    duplicated = duplicate
+    {-# INLINE duplicated #-}
+
 instance Semigroup b => Semigroup (Fold a b) where
     (<>) = liftA2 (<>)
     {-# INLINE (<>) #-}
@@ -396,6 +401,10 @@
         in  FoldM step begin done
     {-# INLINE (<*>) #-}
 
+instance Monad m => Extend (FoldM m a) where
+    duplicated = duplicateM
+    {-# INLINE duplicated #-}
+
 instance Functor m => Profunctor (FoldM m) where
     rmap = fmap
     lmap f (FoldM step begin done) = FoldM step' begin done
@@ -798,14 +807,14 @@
 random = FoldM step begin done
   where
     begin = do
-        g <- createSystemRandom
+        g <- newStdGen
         return $! Pair3 g Nothing' (1 :: Int)
 
     step (Pair3 g Nothing'  _) a = return $! Pair3 g (Just' a) 2
     step (Pair3 g (Just' a) m) b = do
-        n <- uniformR (1, m) g
+        let (n, g') = uniformR (1, m) g
         let c = if n == 1 then b else a
-        return $! Pair3 g (Just' c) (m + 1)
+        return $! Pair3 g' (Just' c) (m + 1)
 
     done (Pair3 _ ma _) = return (lazy ma)
 {-# INLINABLE random #-}
@@ -816,7 +825,7 @@
     { _size      ::                !VectorState
     , _reservoir ::                !(Mutable v RealWorld a)
     , _position  :: {-# UNPACK #-} !Int
-    , _gen       :: {-# UNPACK #-} !GenIO
+    , _gen       :: {-# UNPACK #-} !StdGen
     }
 
 -- | Pick several random elements, using reservoir sampling
@@ -832,15 +841,15 @@
         let s  = if n <= m' then Complete else Incomplete m'
         return $! RandomNState s mv (i + 1) g
     step (RandomNState  Complete      mv i g) a = do
-        r <- uniformR (0, i - 1) g
+        let (r, g') = uniformR (0, i - 1) g
         if r < n
             then M.unsafeWrite mv r a
             else return ()
-        return (RandomNState Complete mv (i + 1) g)
+        return (RandomNState Complete mv (i + 1) g')
 
     begin = do
         mv  <- M.new n
-        gen <- createSystemRandom
+        gen <- newStdGen
         let s = if n <= 0 then Complete else Incomplete 0
         return (RandomNState s mv 1 gen)