diff --git a/Data/Functor/Representable/Trie.hs b/Data/Functor/Representable/Trie.hs
--- a/Data/Functor/Representable/Trie.hs
+++ b/Data/Functor/Representable/Trie.hs
@@ -136,6 +136,9 @@
 instance Functor (Entry a) where
   fmap f (Entry a b) = Entry a (f b)
 
+instance Lookup ((:->:)e) where
+  lookup = lookupDefault
+
 instance Indexable ((:->:)e) where
   index (Trie f) = index f . embedKey
 
diff --git a/representable-tries.cabal b/representable-tries.cabal
--- a/representable-tries.cabal
+++ b/representable-tries.cabal
@@ -1,6 +1,6 @@
 name:          representable-tries
 category:      Data Structures, Functors, Monads, Comonads
-version:       0.3.7
+version:       0.5.0
 license:       BSD3
 cabal-version: >= 1.6
 license-file:  LICENSE
@@ -19,16 +19,16 @@
 
 library
   build-depends: 
-    adjunctions >= 0.9.2 && < 0.10,
+    adjunctions >= 1.0.0 && < 1.0.1,
     base >= 4 && < 4.4,
     bifunctors >= 0.1.1 && < 0.2,
     comonad >= 1.1 && < 1.2,
-    comonad-transformers >= 1.6.3 && < 1.7.0,
+    comonad-transformers >= 1.7 && < 1.8,
     containers >= 0.3 && < 0.5,
     distributive >= 0.2 && < 0.3,
-    keys >= 0.2.7 && < 0.3,
+    keys >= 0.3 && < 0.4,
     mtl >= 2.0.1.0 && < 2.1,
-    representable-functors >= 0.4.4 && < 0.5,
+    representable-functors >= 0.5 && < 0.6,
     semigroups >= 0.5 && < 0.6,
     semigroupoids >= 1.2.2 && < 1.3.0,
     streams >= 0.7.1 && < 0.8,