diff --git a/int-like.cabal b/int-like.cabal
--- a/int-like.cabal
+++ b/int-like.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           int-like
-version:        0.3.0
+version:        0.3.1
 synopsis:       Newtype wrappers over IntSet and IntMap
 description:    Please see the README on GitHub at <https://github.com/ejconlon/int-like#readme>
 category:       Data Structures
diff --git a/src/IntLike/Graph.hs b/src/IntLike/Graph.hs
--- a/src/IntLike/Graph.hs
+++ b/src/IntLike/Graph.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module IntLike.Graph
   ( IntLikeGraph (..)
   , adjacencyIntMultiMap
@@ -16,7 +18,9 @@
 import Algebra.Graph.Class (Graph (..))
 import Control.DeepSeq (NFData)
 import Data.Coerce (Coercible, coerce)
+#if !MIN_VERSION_base(4,20,0) /* foldl' migration */
 import Data.Foldable (foldl')
+#endif
 import Data.Hashable (Hashable)
 import Data.Tuple (swap)
 import IntLike.Equiv (IntLikeEquiv)
diff --git a/src/IntLike/Map.hs b/src/IntLike/Map.hs
--- a/src/IntLike/Map.hs
+++ b/src/IntLike/Map.hs
@@ -184,7 +184,17 @@
 import Data.IntMap.Strict (IntMap)
 import qualified Data.IntMap.Strict as IntMap
 import IntLike.Set (IntLikeSet (..))
-import Prelude hiding (filter, foldl, foldr, lookup, map, null)
+import Prelude hiding
+  ( filter
+  , foldl
+#if MIN_VERSION_base(4,20,0) /* foldl' migration */
+  , foldl'
+#endif
+  , foldr
+  , lookup
+  , map
+  , null
+  )
 
 type role IntLikeMap nominal representational
 
diff --git a/src/IntLike/MultiMap.hs b/src/IntLike/MultiMap.hs
--- a/src/IntLike/MultiMap.hs
+++ b/src/IntLike/MultiMap.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module IntLike.MultiMap
   ( IntLikeMultiMap
   , empty
@@ -13,7 +15,9 @@
 
 import Control.Monad (foldM)
 import Data.Coerce (Coercible)
+#if !MIN_VERSION_base(4,20,0) /* foldl' migration */
 import Data.Foldable (foldl')
+#endif
 import IntLike.Map (IntLikeMap)
 import qualified IntLike.Map as ILM
 import IntLike.Set (IntLikeSet)
diff --git a/src/IntLike/Set.hs b/src/IntLike/Set.hs
--- a/src/IntLike/Set.hs
+++ b/src/IntLike/Set.hs
@@ -113,7 +113,17 @@
 #if MIN_VERSION_containers(0,8,0)
 import Data.List.NonEmpty (NonEmpty)
 #endif
-import Prelude hiding (filter, foldMap, foldl, foldr, map, null)
+import Prelude hiding
+  ( filter
+  , foldMap
+  , foldl
+#if MIN_VERSION_base(4,20,0) /* foldl' migration */
+  , foldl'
+#endif
+  , foldr
+  , map
+  , null
+  )
 
 type role IntLikeSet nominal