diff --git a/sets.cabal b/sets.cabal
--- a/sets.cabal
+++ b/sets.cabal
@@ -1,24 +1,24 @@
--- This file has been generated from package.yaml by hpack version 0.21.2.
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.31.2.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 9b097802837c1541d33b7338721f7e72c397c26e7eb80b8148a1a0299dac9450
+-- hash: a07ff46d2ef6defe85f666d93492fcc0cba3c4ab46d08ee7d34dcee21a1362de
 
 name:           sets
-version:        0.0.6.1
+version:        0.0.6.2
 synopsis:       Ducktyped set interface for Haskell containers.
 description:    Please see the README on Github at <https://github.com/athanclark/sets#readme>
 category:       Data
 homepage:       https://github.com/athanclark/sets#readme
 bug-reports:    https://github.com/athanclark/sets/issues
 author:         Athan Clark
-maintainer:     athan.clark@localcooking.com
+maintainer:     athan.clark@gmail.com
 copyright:      2018 Athan Clark
 license:        BSD3
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.10
-
 extra-source-files:
     README.md
 
diff --git a/src/Data/Set/Ordered/Many/With.hs b/src/Data/Set/Ordered/Many/With.hs
--- a/src/Data/Set/Ordered/Many/With.hs
+++ b/src/Data/Set/Ordered/Many/With.hs
@@ -14,6 +14,7 @@
 import qualified Data.Set.Ordered.Many as OM
 import qualified Data.Set.Ordered.Unique.With as OU
 import qualified Data.Map as Map
+import qualified Data.Map.Internal.Debug as MapDebug
 import qualified Data.Witherable as Wither
 
 import Data.Monoid
@@ -272,7 +273,7 @@
 -- -- ** Legacy Fold
 
 fold :: Fold.Foldable c => (a -> b -> b) -> b -> SetsWith k c a -> b
-fold f acc (SetsWith (_,xs)) = Map.fold go acc xs
+fold f acc (SetsWith (_,xs)) = Map.foldr go acc xs
   where
     go cs acc' = Fold.foldr f acc' cs
 
@@ -341,7 +342,7 @@
 -- -- * Debugging
 
 showTree :: (Show k, Show (c a)) => SetsWith k c a -> String
-showTree (SetsWith (_,xs)) = Map.showTree xs
+showTree (SetsWith (_,xs)) = MapDebug.showTree xs
 
 showTreeWith :: (k -> c a -> String) -> Bool -> Bool -> SetsWith k c a -> String
-showTreeWith f a b (SetsWith (_,xs)) = Map.showTreeWith f a b xs
+showTreeWith f a b (SetsWith (_,xs)) = MapDebug.showTreeWith f a b xs
diff --git a/src/Data/Set/Ordered/Unique/With.hs b/src/Data/Set/Ordered/Unique/With.hs
--- a/src/Data/Set/Ordered/Unique/With.hs
+++ b/src/Data/Set/Ordered/Unique/With.hs
@@ -16,6 +16,7 @@
 import Prelude ( Show, String, Eq, Ord, Bool, Int, Maybe
                , fmap, not, fst, snd, zip, (.), ($), foldr)
 import qualified Data.Map as Map
+import qualified Data.Map.Internal.Debug as MapDebug
 import qualified Data.List as List
 import Data.Maybe (isJust)
 import qualified Data.Foldable as Fold
@@ -162,7 +163,7 @@
 -- ** Legacy Fold
 
 fold :: (a -> b -> b) -> b -> SetWith k a -> b
-fold f acc (SetWith (_,xs)) = Map.fold f acc xs
+fold f acc (SetWith (_,xs)) = Map.foldr f acc xs
 
 -- * Min/Max
 
@@ -220,7 +221,7 @@
 -- * Debugging
 
 showTree :: (Show k, Show a) => SetWith k a -> String
-showTree (SetWith (_,xs)) = Map.showTree xs
+showTree (SetWith (_,xs)) = MapDebug.showTree xs
 
 showTreeWith :: (k -> a -> String) -> Bool -> Bool -> SetWith k a -> String
-showTreeWith f a b (SetWith (_,xs)) = Map.showTreeWith f a b xs
+showTreeWith f a b (SetWith (_,xs)) = MapDebug.showTreeWith f a b xs