diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,11 @@
+0.6
+-----------------------------------------------------------------------------
+- Update to `exceptions` 0.6
+
+0.5.1
+-----------------------------------------------------------------------------
+- Constrain `exceptions` dependency to < 0.6
+
 0.5
 -----------------------------------------------------------------------------
 - bugfix release (#44, PR #47) which exposes `DontWait` flag on Windows
diff --git a/src/System/ZMQ4/Monadic.hs b/src/System/ZMQ4/Monadic.hs
--- a/src/System/ZMQ4/Monadic.hs
+++ b/src/System/ZMQ4/Monadic.hs
@@ -234,6 +234,7 @@
 instance MonadCatch (ZMQ z) where
     catch (ZMQ m) f = ZMQ $ m `C.catch` (_unzmq . f)
 
+instance MonadMask (ZMQ z) where
     mask a = ZMQ . ReaderT $ \env ->
         C.mask $ \restore ->
             let f (ZMQ (ReaderT b)) = ZMQ $ ReaderT (restore . b)
diff --git a/zeromq4-haskell.cabal b/zeromq4-haskell.cabal
--- a/zeromq4-haskell.cabal
+++ b/zeromq4-haskell.cabal
@@ -1,5 +1,5 @@
 name:               zeromq4-haskell
-version:            0.5.1
+version:            0.6
 synopsis:           Bindings to ZeroMQ 4.x
 category:           System, FFI
 license:            MIT
@@ -57,7 +57,7 @@
         , async        == 2.0.*
         , bytestring
         , containers
-        , exceptions   >= 0.4 && < 0.6
+        , exceptions   == 0.6.*
         , semigroups   >= 0.8
         , transformers >= 0.3