diff --git a/Control/Arrow/Abort.hs b/Control/Arrow/Abort.hs
--- a/Control/Arrow/Abort.hs
+++ b/Control/Arrow/Abort.hs
@@ -5,7 +5,7 @@
 import Control.Monad;
 import Control.Category;
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 import Control.Arrow.Abort.Class;
 
 newtype AbortT v r a b = AbortT { unwrapAbortT :: r a (Either v b) };
@@ -13,7 +13,7 @@
 runAbortT :: Arrow r => AbortT v r a v -> r a v;
 runAbortT = (>>> arr (either id id)) . unwrapAbortT;
 
-instance ArrowTrans (AbortT v) where {
+instance ArrowTransformer (AbortT v) where {
   lift = AbortT . (>>> arr Right);
   tmap f = AbortT . f . unwrapAbortT;
 };
@@ -33,6 +33,6 @@
   abort = AbortT $ arr Left;
 };
 
-instance (ArrowChoice r, ArrowTrans xT, Arrow (xT (AbortT v r))) => ArrowAbort v (xT (AbortT v r)) where {
+instance (ArrowChoice r, ArrowTransformer xT, Arrow (xT (AbortT v r))) => ArrowAbort v (xT (AbortT v r)) where {
   abort = lift abort;
 };
diff --git a/Control/Arrow/Abort/Class.hs b/Control/Arrow/Abort/Class.hs
--- a/Control/Arrow/Abort/Class.hs
+++ b/Control/Arrow/Abort/Class.hs
@@ -3,7 +3,7 @@
 module Control.Arrow.Abort.Class where
 
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 
 class Arrow r => ArrowAbort v r | r -> v where {
   abort :: r v a; -- terminate with final value
diff --git a/Control/Arrow/List/Class.hs b/Control/Arrow/List/Class.hs
--- a/Control/Arrow/List/Class.hs
+++ b/Control/Arrow/List/Class.hs
@@ -1,7 +1,7 @@
 module Control.Arrow.List.Class where
 
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 
 class Arrow r => ArrowList r where {
   arrL :: ( a  -> [b]) -> r a b;
diff --git a/Control/Arrow/Reader.hs b/Control/Arrow/Reader.hs
--- a/Control/Arrow/Reader.hs
+++ b/Control/Arrow/Reader.hs
@@ -5,7 +5,7 @@
 import Control.Monad;
 import Control.Category;
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 import Control.Arrow.Reader.Class;
 
 newtype ReaderT r s a b = ReaderT { runReaderT :: r -> s a b };
@@ -16,7 +16,7 @@
 outlineReaderT :: (Arrow s) => s (r, a) b -> ReaderT r s a b;
 outlineReaderT = ReaderT . flip ((>>>) . arr . (&&& id) . const);
 
-instance ArrowTrans (ReaderT r) where {
+instance ArrowTransformer (ReaderT r) where {
   lift = ReaderT . const;
   tmap f = ReaderT . liftM f . runReaderT;
 };
@@ -41,7 +41,7 @@
   local = withReaderT;
 };
 
-instance (Arrow s, ArrowTrans xT, Arrow (xT (ReaderT r s))) => ArrowReader r (xT (ReaderT r s)) where {
+instance (Arrow s, ArrowTransformer xT, Arrow (xT (ReaderT r s))) => ArrowReader r (xT (ReaderT r s)) where {
   ask   = lift ask;
   local = undefined;
 };
diff --git a/Control/Arrow/Reader/Class.hs b/Control/Arrow/Reader/Class.hs
--- a/Control/Arrow/Reader/Class.hs
+++ b/Control/Arrow/Reader/Class.hs
@@ -3,7 +3,7 @@
 module Control.Arrow.Reader.Class where
 
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 
 class Arrow s => ArrowReader r s | s -> r where {
   ask :: s () r;
diff --git a/Control/Arrow/State.hs b/Control/Arrow/State.hs
--- a/Control/Arrow/State.hs
+++ b/Control/Arrow/State.hs
@@ -3,13 +3,13 @@
 import Prelude hiding ((.), id);
 
 import Control.Arrow;
-import Control.Arrow.Trans;
+import Control.Arrow.Transformer;
 import Control.Arrow.State.Class;
 import Control.Category;
 
 newtype StateT s r a b = StateT { runStateT :: r (a, s) (b, s) };
 
-instance ArrowTrans (StateT s) where {
+instance ArrowTransformer (StateT s) where {
   lift = StateT . (*** id);
   tmap f = StateT . f . runStateT;
 };
@@ -36,7 +36,7 @@
   put = StateT $ arr $ \ (s, _) -> ((), s);
 };
 
-instance (Arrow r, ArrowTrans xT, Arrow (xT (StateT s r))) => ArrowState s (xT (StateT s r)) where {
+instance (Arrow r, ArrowTransformer xT, Arrow (xT (StateT s r))) => ArrowState s (xT (StateT s r)) where {
   get = lift get;
   put = lift put;
 };
diff --git a/Control/Arrow/Trans.hs b/Control/Arrow/Trans.hs
deleted file mode 100644
--- a/Control/Arrow/Trans.hs
+++ /dev/null
@@ -1,10 +0,0 @@
-{-# LANGUAGE ExistentialQuantification #-}
-
-module Control.Arrow.Trans where
-
-import Control.Arrow;
-
-class ArrowTrans xT where {
-  lift :: Arrow r => r a b -> xT r a b;
-  tmap :: (Arrow r, Arrow s) => (∀ a b . r a b -> s a b) -> xT r a b -> xT s a b;
-};
diff --git a/Control/Arrow/Transformer.hs b/Control/Arrow/Transformer.hs
new file mode 100644
--- /dev/null
+++ b/Control/Arrow/Transformer.hs
@@ -0,0 +1,10 @@
+{-# LANGUAGE ExistentialQuantification #-}
+
+module Control.Arrow.Transformer where
+
+import Control.Arrow;
+
+class ArrowTransformer xT where {
+  lift :: Arrow r => r a b -> xT r a b;
+  tmap :: (Arrow r, Arrow s) => (∀ a b . r a b -> s a b) -> xT r a b -> xT s a b;
+};
diff --git a/atl.cabal b/atl.cabal
--- a/atl.cabal
+++ b/atl.cabal
@@ -1,5 +1,5 @@
 Name:atl
-Version:15310.92
+Version:15320.1
 Description:Arrow Transformer Library
 License:LGPL
 License-File:license.txt
@@ -13,5 +13,5 @@
 Library {
   Build-Depends: base >= 4 && < 5
   Extensions: UnicodeSyntax, RankNTypes, MultiParamTypeClasses, FlexibleInstances, FlexibleContexts
-  Exposed-Modules: Control.Arrow.Trans, Control.Arrow.Reader, Control.Arrow.Reader.Class, Control.Arrow.List.Class, Control.Arrow.Abort, Control.Arrow.Abort.Class, Control.Arrow.State, Control.Arrow.State.Class
+  Exposed-Modules: Control.Arrow.Transformer, Control.Arrow.Reader, Control.Arrow.Reader.Class, Control.Arrow.List.Class, Control.Arrow.Abort, Control.Arrow.Abort.Class, Control.Arrow.State, Control.Arrow.State.Class
 }