diff --git a/Data/Invertible/Monoid.hs b/Data/Invertible/Monoid.hs
--- a/Data/Invertible/Monoid.hs
+++ b/Data/Invertible/Monoid.hs
@@ -1,5 +1,6 @@
 -- |
 -- Bidirectional transforms for "Data.Monoid".
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE Safe, TypeOperators, QuasiQuotes #-}
 module Data.Invertible.Monoid
   ( BiEndo(..)
@@ -32,6 +33,11 @@
 
 -- | The monoid of endomorphisms under composition.
 newtype BiEndo a = BiEndo { appBiEndo :: a <-> a }
+
+#if MIN_VERSION_base(4,11,0)
+instance Semigroup (BiEndo a) where
+  BiEndo f <> BiEndo g = BiEndo (f C.. g)
+#endif
 
 instance Monoid (BiEndo a) where
   mempty = BiEndo C.id
diff --git a/Data/Invertible/TH.hs b/Data/Invertible/TH.hs
--- a/Data/Invertible/TH.hs
+++ b/Data/Invertible/TH.hs
@@ -51,6 +51,9 @@
 patToExp (TH.VarP v) = TH.VarE v
 patToExp (TH.TupP l) = TH.TupE $ map patToExp l
 patToExp (TH.UnboxedTupP l) = TH.UnboxedTupE $ map patToExp l
+#if MIN_VERSION_template_haskell(2,12,0)
+patToExp (TH.UnboxedSumP p a n) = TH.UnboxedSumE (patToExp p) a n
+#endif
 patToExp (TH.ConP c a) = foldl (\f -> TH.AppE f . patToExp) (TH.ConE c) a
 patToExp (TH.InfixP l o r) = TH.InfixE (Just $ patToExp l) (TH.ConE o) (Just $ patToExp r)
 patToExp (TH.UInfixP l o r) = TH.UInfixE (patToExp l) (TH.ConE o) (patToExp r)
diff --git a/invertible.cabal b/invertible.cabal
--- a/invertible.cabal
+++ b/invertible.cabal
@@ -1,5 +1,5 @@
 name:                invertible
-version:             0.2.0.3
+version:             0.2.0.4
 synopsis:            bidirectional arrows, bijective functions, and invariant functors
 description:
   Representations and operations for bidirectional arrows (total isomorphisms: an