diff --git a/servant-ruby.cabal b/servant-ruby.cabal
--- a/servant-ruby.cabal
+++ b/servant-ruby.cabal
@@ -1,5 +1,5 @@
 name:                servant-ruby
-version:             0.2.1.0
+version:             0.3.0.0
 synopsis:            Generate a Ruby client from a Servant API with Net::HTTP.
 description:         Generate a Ruby client from a Servant API with Net::HTTP.
 homepage:            https://github.com/joneshf/servant-ruby#readme
@@ -31,7 +31,8 @@
   main-is:             Main.hs
   hs-source-dirs:      test
   build-depends:       base
-                     , doctest >= 0.11 && < 0.12
+                     , doctest >= 0.11 && < 0.13
+                     , QuickCheck >= 2.9 && < 2.10
   default-language:    Haskell2010
 
 source-repository head
diff --git a/src/Servant/Ruby.hs b/src/Servant/Ruby.hs
--- a/src/Servant/Ruby.hs
+++ b/src/Servant/Ruby.hs
@@ -320,5 +320,8 @@
   key = qarg ^. queryArgName.argName._PathSegment
   val = snake key
 
+{-|
+prop> \str -> snake (snake $ T.pack str) == snake (T.pack str)
+-}
 snake :: Text -> Text
 snake = T.pack . quietSnake . T.unpack