diff --git a/hw-prim.cabal b/hw-prim.cabal
--- a/hw-prim.cabal
+++ b/hw-prim.cabal
@@ -1,7 +1,7 @@
 cabal-version:  2.2
 
 name:           hw-prim
-version:        0.6.2.30
+version:        0.6.2.31
 synopsis:       Primitive functions and data types
 description:    Primitive functions and data types.
 category:       Data
diff --git a/src/HaskellWorks/Control/Monad/Lazy.hs b/src/HaskellWorks/Control/Monad/Lazy.hs
--- a/src/HaskellWorks/Control/Monad/Lazy.hs
+++ b/src/HaskellWorks/Control/Monad/Lazy.hs
@@ -1,6 +1,9 @@
+{-# LANGUAGE BangPatterns #-}
 module HaskellWorks.Control.Monad.Lazy
   ( interleaveSequenceIO
   , interleaveSequenceM
+  , interleaveUnfoldrM
+  , interleaveTraverseM
   ) where
 
 import Control.Monad.IO.Unlift
@@ -18,3 +21,36 @@
 interleaveSequenceM as = do
   f <- askUnliftIO
   liftIO $ interleaveSequenceIO (fmap (unliftIO f) as)
+
+-- | Generates a lazy list of values that are produced by a given monadic function.
+--
+-- This function is intended to be like the "standard" 'unfoldrM' except
+-- that the list is generated lazily.
+interleaveUnfoldrM :: MonadUnliftIO m => (b -> m (Maybe (a, b))) -> b -> m [a]
+interleaveUnfoldrM f z = do
+  u <- askUnliftIO
+  liftIO $ IO.unsafeInterleaveIO (go u z)
+  where
+    go !u !b = do
+      m <- unliftIO u (f b)
+      case m of
+        Nothing      -> pure []
+        Just (!a, b') -> do
+          rest <- IO.unsafeInterleaveIO (go u b')
+          pure (a:rest)
+
+-- | Traverses the function over the list and produces a lazy list in a
+-- monadic context.
+--
+-- It is intended to be like the "standard" 'traverse' except
+-- that the list is generated lazily.
+interleaveTraverseM :: MonadUnliftIO m => (a -> m b) -> [a] -> m [b]
+interleaveTraverseM f as = do
+  u <- askUnliftIO
+  liftIO $ IO.unsafeInterleaveIO (go u as)
+  where
+    go _ [] = pure []
+    go !u (v:vs) = do
+      !res <- unliftIO u (f v)
+      rest <- IO.unsafeInterleaveIO (go u vs)
+      pure (res:rest)