diff --git a/fixed-length.cabal b/fixed-length.cabal
--- a/fixed-length.cabal
+++ b/fixed-length.cabal
@@ -1,5 +1,5 @@
 Name:             fixed-length
-Version:          0.0.0.2
+Version:          0.1
 License:          BSD3
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
@@ -25,7 +25,7 @@
 Build-Type:       Simple
 
 Source-Repository this
-  Tag:         0.0.0.2
+  Tag:         0.1
   Type:        darcs
   Location:    http://code.haskell.org/~thielema/fixed-length/
 
diff --git a/src/Data/FixedLength.hs b/src/Data/FixedLength.hs
--- a/src/Data/FixedLength.hs
+++ b/src/Data/FixedLength.hs
@@ -33,22 +33,27 @@
 import Prelude (Functor, fmap, Show, (+), error)
 
 
+type family List position :: * -> *
+
 class (list ~ List (Position list)) => C list where
    type Position list :: *
-   type List position :: * -> *
    switch ::
       f Empty.T ->
       (forall list0. C list0 => f (NonEmpty.T list0)) ->
       f list
 
+
+type instance List Zero = Empty.T
+
 instance C Empty.T where
    type Position Empty.T = Zero
-   type List Zero = Empty.T
    switch x _ = x
 
+
+type instance List (Succ position) = NonEmpty.T (List position)
+
 instance C list => C (NonEmpty.T list) where
    type Position (NonEmpty.T list) = Succ (Position list)
-   type List (Succ position) = NonEmpty.T (List position)
    switch _ x = x