diff --git a/Control/Joint/Base/Configured.hs b/Control/Joint/Base/Configured.hs
new file mode 100644
--- /dev/null
+++ b/Control/Joint/Base/Configured.hs
@@ -0,0 +1,34 @@
+module Control.Joint.Base.Configured where
+
+import Control.Joint.Composition (Composition (Primary, run))
+import Control.Joint.Transformer (Transformer (Schema, embed, build, unite))
+import Control.Joint.Modulator (Modulator ((-<$>-)))
+import Control.Joint.Schemes.TU (TU (TU))
+
+newtype Configured e a = Configured (e -> a)
+
+instance Functor u => Functor (TU ((->) e) u) where
+	fmap f (TU x) = TU $ \r -> f <$> x r
+
+instance Applicative u => Applicative (TU ((->) e) u) where
+	pure = TU . pure . pure
+	TU f <*> TU x = TU $ \r -> f r <*> x r
+
+instance (Applicative u, Monad u) => Monad (TU ((->) e) u) where
+	TU x >>= f = TU $ \e -> x e >>= ($ e) . run . f
+
+instance Composition (Configured e) where
+	type Primary (Configured e) a = (->) e a
+	run (Configured x) = x
+
+instance Transformer (Configured e) where
+	type Schema (Configured e) u = TU ((->) e) u
+	embed x = TU . const $ x
+	build x = TU $ pure <$> run x
+	unite = TU
+
+instance Modulator (Configured e) where
+	f -<$>- (TU x) = TU $ f <$> x
+
+ask :: Configured e e
+ask = Configured $ \e -> e
diff --git a/Control/Joint/Base/Either.hs b/Control/Joint/Base/Either.hs
--- a/Control/Joint/Base/Either.hs
+++ b/Control/Joint/Base/Either.hs
@@ -1,7 +1,7 @@
 module Control.Joint.Base.Either where
 
 import Control.Joint.Composition (Composition (Primary, run))
-import Control.Joint.Transformer (Transformer (Schema, embed, build))
+import Control.Joint.Transformer (Transformer (Schema, embed, build, unite))
 import Control.Joint.Schemes.UT (UT (UT))
 
 instance Functor u => Functor (UT (Either e) u) where
@@ -22,3 +22,4 @@
 	type Schema (Either e) u = UT (Either e) u
 	embed x = UT $ Right <$> x
 	build x = UT . pure $ x
+	unite = UT
diff --git a/Control/Joint/Base/Maybe.hs b/Control/Joint/Base/Maybe.hs
--- a/Control/Joint/Base/Maybe.hs
+++ b/Control/Joint/Base/Maybe.hs
@@ -1,7 +1,7 @@
 module Control.Joint.Base.Maybe where
 
 import Control.Joint.Composition (Composition (Primary, run))
-import Control.Joint.Transformer (Transformer (Schema, embed, build))
+import Control.Joint.Transformer (Transformer (Schema, embed, build, unite))
 import Control.Joint.Schemes.UT (UT (UT))
 
 instance Functor u => Functor (UT Maybe u) where
@@ -22,3 +22,4 @@
 	type Schema Maybe u = UT Maybe u
 	embed x = UT $ Just <$> x
 	build x = UT . pure $ x
+	unite = UT
diff --git a/Control/Joint/Base/Reader.hs b/Control/Joint/Base/Reader.hs
deleted file mode 100644
--- a/Control/Joint/Base/Reader.hs
+++ /dev/null
@@ -1,26 +0,0 @@
-module Control.Joint.Base.Reader where
-
-import Control.Joint.Composition (Composition (Primary, run))
-import Control.Joint.Transformer (Transformer (Schema, embed, build))
-import Control.Joint.Schemes.TU (TU (TU))
-
-newtype Reader e a = Reader (e -> a)
-
-instance Functor u => Functor (TU ((->) e) u) where
-	fmap f (TU x) = TU $ \r -> f <$> x r
---
-instance Applicative u => Applicative (TU ((->) e) u) where
-	pure = TU . pure . pure
-	TU f <*> TU x = TU $ \r -> f r <*> x r
-
-instance (Applicative u, Monad u) => Monad (TU ((->) e) u) where
-	TU x >>= f = TU $ \e -> x e >>= ($ e) . run . f
-
-instance Composition (Reader e) where
-	type Primary (Reader e) a = (->) e a
-	run (Reader x) = x
-
-instance Transformer (Reader e) where
-	type Schema (Reader e) u = TU ((->) e) u
-	embed x = TU . const $ x
-	build x = TU $ pure <$> run x
diff --git a/Control/Joint/Base/State.hs b/Control/Joint/Base/State.hs
--- a/Control/Joint/Base/State.hs
+++ b/Control/Joint/Base/State.hs
@@ -2,7 +2,7 @@
 
 import Control.Joint.Core (type (:.), type (:=))
 import Control.Joint.Composition (Composition (Primary, run))
-import Control.Joint.Transformer (Transformer (Schema, embed, build))
+import Control.Joint.Transformer (Transformer (Schema, embed, build, unite))
 import Control.Joint.Schemes.TUT (TUT (TUT))
 
 newtype State s a = State ((->) s :. (,) s := a)
@@ -31,6 +31,7 @@
 	type Schema (State s) u = TUT ((->) s) u ((,) s)
 	embed x = TUT $ \s -> (s,) <$> x
 	build x = TUT $ pure <$> run x
+	unite = TUT
 
 instance Functor u => Functor (TUT ((->) s) u ((,) s)) where
 	fmap f (TUT x) = TUT $ \old -> (fmap . fmap) f $ x old
diff --git a/Control/Joint/Modulator.hs b/Control/Joint/Modulator.hs
new file mode 100644
--- /dev/null
+++ b/Control/Joint/Modulator.hs
@@ -0,0 +1,7 @@
+module Control.Joint.Modulator where
+
+import Control.Joint.Transformer (Transformer (Schema))
+
+class Transformer t => Modulator t where
+	{-# MINIMAL (-<$>-) #-}
+	(-<$>-) :: (u a -> v b) -> Schema t u a -> Schema t v b
diff --git a/Control/Joint/Transformer.hs b/Control/Joint/Transformer.hs
--- a/Control/Joint/Transformer.hs
+++ b/Control/Joint/Transformer.hs
@@ -1,13 +1,14 @@
 module Control.Joint.Transformer (Transformer (..), type (:>)) where
 
 import Control.Joint.Core (type (~>))
-import Control.Joint.Composition (Composition)
+import Control.Joint.Composition (Composition (Primary))
 
 class Composition t => Transformer t where
-	{-# MINIMAL embed, build #-}
+	{-# MINIMAL embed, build, unite #-}
 	type Schema (t :: * -> *) (u :: * -> *) = (r :: * -> *) | r -> t u
 	embed :: Functor u => u ~> Schema t u
 	build :: Applicative u => t ~> Schema t u
+	unite :: Primary (Schema t u) a -> Schema t u a
 
 infixr 1 :>
 type (:>) t u a = Transformer t => Schema t u a
diff --git a/joint.cabal b/joint.cabal
--- a/joint.cabal
+++ b/joint.cabal
@@ -1,5 +1,5 @@
 name:                joint
-version:             0.1.2
+version:             0.1.3
 synopsis:            Trying to compose non-composable
 homepage:            https://github.com/iokasimov/joint
 license:             BSD3
@@ -20,13 +20,14 @@
     Control.Joint.Core
     Control.Joint.Composition
     Control.Joint.Transformer
+    Control.Joint.Modulator
     Control.Joint.Schemes
     Control.Joint.Schemes.TU
     Control.Joint.Schemes.UT
     Control.Joint.Schemes.TUT
+    Control.Joint.Base.Configured
     Control.Joint.Base.Maybe
     Control.Joint.Base.Either
-    Control.Joint.Base.Reader
     Control.Joint.Base.State
   build-depends: base == 4.*
   default-language: Haskell2010