diff --git a/TestTypes.hs b/TestTypes.hs
new file mode 100644
--- /dev/null
+++ b/TestTypes.hs
@@ -0,0 +1,12 @@
+module TestTypes where
+
+data U a b c d
+    = L [U a b c d]               -- polymorphic recursion
+    | M (V (a,b) (Either c d))    -- mutually recursive
+    | a :+: Int                   -- infix syntax, record syntax, type synonyms
+    | R { c :: c, d :: String }   -- and primitive data types supported
+ deriving (Eq,Show)
+
+data V u v = X (U v v u u) | Z u
+ deriving (Eq,Show)
+
diff --git a/genifunctors.cabal b/genifunctors.cabal
--- a/genifunctors.cabal
+++ b/genifunctors.cabal
@@ -1,5 +1,5 @@
 name:                genifunctors
-version:             0.2.0.0
+version:             0.2.1.0
 synopsis:            Generate generalized fmap, foldMap and traverse
 description:         Generate (derive) fmap, foldMap and traverse for Bifunctors, Trifunctors, or a functor with any arity
 license:             BSD3
@@ -11,6 +11,7 @@
 cabal-version:       >=1.10
 homepage:            https://github.com/danr/genifunctors
 bug-reports:         https://github.com/danr/genifunctors/issues
+extra-source-files:  TestTypes.hs
 
 source-repository head
   type: git