diff --git a/Unbound/LocallyNameless/Fresh.hs b/Unbound/LocallyNameless/Fresh.hs
--- a/Unbound/LocallyNameless/Fresh.hs
+++ b/Unbound/LocallyNameless/Fresh.hs
@@ -82,7 +82,7 @@
 --   still globally unused, and increments the index every time it is
 --   asked for a fresh name.
 newtype FreshMT m a = FreshMT { unFreshMT :: St.StateT Integer m a }
-  deriving (Functor, Applicative, Monad, St.MonadState Integer, MonadPlus, MonadIO)
+  deriving (Functor, Applicative, Monad, St.MonadState Integer, MonadPlus, MonadIO, MonadFix)
 
 -- | Run a 'FreshMT' computation (with the global index starting at zero).
 runFreshMT :: Monad m => FreshMT m a -> m a
@@ -182,7 +182,7 @@
 -- avoid, and when asked for a fresh one will choose the first numeric
 -- prefix of the given name which is currently unused.
 newtype LFreshMT m a = LFreshMT { unLFreshMT :: ReaderT (Set AnyName) m a }
-  deriving (Functor, Applicative, Monad, MonadReader (Set AnyName), MonadIO, MonadPlus)
+  deriving (Functor, Applicative, Monad, MonadReader (Set AnyName), MonadIO, MonadPlus, MonadFix)
 
 -- | Run an 'LFreshMT' computation in an empty context.
 runLFreshMT :: LFreshMT m a -> m a
diff --git a/unbound.cabal b/unbound.cabal
--- a/unbound.cabal
+++ b/unbound.cabal
@@ -1,5 +1,5 @@
 name:           unbound
-version:        0.2.1
+version:        0.2.2
 license:        BSD3
 license-file:   LICENSE
 build-type:     Simple