diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Changelog for path-like
 
+## (v0.1.2.0)
+
+* Change to ConstraintKinds style.
+
 ## (v0.1.1.0)
 
 * Add 'PathLike` superclass to `FileLike` and `DirLike`.
diff --git a/path-like.cabal b/path-like.cabal
--- a/path-like.cabal
+++ b/path-like.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           path-like
-version:        0.1.1.0
+version:        0.1.2.0
 synopsis:       PathLike, FileLike and DirLike type classes for the Path library.
 description:    Type classes for the Path library. Exports PathLike, FileLike and DirLike classes so that stricter types may be used as Paths.
 category:       Filesystem
diff --git a/src/Path/Like.hs b/src/Path/Like.hs
--- a/src/Path/Like.hs
+++ b/src/Path/Like.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE ConstraintKinds        #-}
 {-# LANGUAGE FlexibleContexts       #-}
 {-# LANGUAGE FlexibleInstances      #-}
 {-# LANGUAGE FunctionalDependencies #-}
@@ -14,8 +15,10 @@
 
 module Path.Like (
   PathLike(..)
-, FileLike(..)
-, DirLike(..)
+, FileLike
+, DirLike
+, toFile
+, toDir
 , (/>)
 ) where
 
@@ -25,21 +28,14 @@
 class PathLike b t a | a -> b, a -> t where
   toPath :: a -> Path b t
 
--- | Class representing a type `a` that can be compiled down to a `Path b File`.
-class PathLike b File a => FileLike b a where
-  toFile :: a -> Path b File
-  toFile = toPath
-
--- | Class repreenting a type `a` that can be compiled down to a `Path b Dir`.
-class PathLike b Dir a => DirLike b a where
-  toDir :: a -> Path b Dir
-  toDir = toPath
+type FileLike b a = PathLike b File a
+type DirLike b a = PathLike b Dir a
 
-instance PathLike b t (Path b t) where
-  toPath = id
+toFile :: FileLike b a => a -> Path b File
+toFile = toPath
 
-instance FileLike b (Path b File)
-instance DirLike b (Path b Dir)
+toDir :: DirLike b a  => a -> Path b Dir
+toDir = toPath
 
 -- | Like `Path.</>`, but works for any `DirLike` and relative `FileLike` to produce a concrete `Path`.
 (/>) :: (DirLike b a, FileLike Rel c) => a -> c -> Path b File