diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,7 @@
+0.9.1.1
+-------
+* Updated to work with `bifunctors` 4.0
+
 0.9.1
 -----
 * Updated to work with `comonad` 4.0 and `profunctors` 4.0
diff --git a/bound.cabal b/bound.cabal
--- a/bound.cabal
+++ b/bound.cabal
@@ -1,6 +1,6 @@
 name:          bound
 category:      Language, Compilers/Interpreters
-version:       0.9.1
+version:       0.9.1.1
 license:       BSD3
 cabal-version: >= 1.9.2
 license-file:  LICENSE
@@ -66,7 +66,7 @@
 
   build-depends:
     base            >= 4       && < 5,
-    bifunctors      >= 3       && < 4,
+    bifunctors      >= 3       && < 5,
     binary          >= 0.5     && < 0.8,
     bytes           >= 0.4     && < 1,
     cereal          >= 0.3.5.2 && < 0.5,