diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,2 +1,2 @@
 # hw-parser
-[![0.0-branch](https://circleci.com/gh/haskell-works/hw-parser/tree/0.0-branch.svg?style=svg)](https://circleci.com/gh/haskell-works/hw-parser/tree/0.0-branch)
+[![master](https://circleci.com/gh/haskell-works/hw-parser/tree/master.svg?style=svg)](https://circleci.com/gh/haskell-works/hw-parser/tree/master)
diff --git a/hw-parser.cabal b/hw-parser.cabal
--- a/hw-parser.cabal
+++ b/hw-parser.cabal
@@ -1,31 +1,62 @@
-name:                   hw-parser
-version:                0.0.0.3
-synopsis:               Simple parser support
-description:            Please see README.md
-homepage:               http://github.com/haskell-works/hw-parser#readme
-license:                BSD3
-license-file:           LICENSE
-author:                 John Ky
-maintainer:             newhoggy@gmail.com
-copyright:              2016 John Ky
-category:               Data, Parser
-build-type:             Simple
-extra-source-files:     README.md
-cabal-version:          >= 1.22
+cabal-version:  2.2
 
-library
-  hs-source-dirs:       src
-  exposed-modules:      HaskellWorks.Data.Parser
-  build-depends:        base                          >= 4          && < 5
-                      , attoparsec
-                      , bytestring
-                      , hw-prim                       >= 0.4.0.0
-                      , mono-traversable
-                      , text
+name:           hw-parser
+version:        0.0.0.4
+synopsis:       Simple parser support
+description:    Simple parser support. Please see README.md
+category:       Data, Parser
+homepage:       http://github.com/haskell-works/hw-parser#readme
+bug-reports:    https://github.com/haskell-works/hw-parser/issues
+author:         John Ky
+maintainer:     newhoggy@gmail.com
+copyright:      2016-2019 John Ky
+license:        BSD-3-Clause
+license-file:   LICENSE
+tested-with:    GHC == 8.8.1, GHC == 8.6.5, GHC == 8.4.4, GHC == 8.2.2
+build-type:     Simple
 
-  default-language:     Haskell2010
-  ghc-options:          -Wall -msse4.2
+extra-source-files:
+    README.md
 
 source-repository head
-  type:     git
+  type: git
   location: https://github.com/haskell-works/hw-parser
+
+common base                 { build-depends: base                 >= 4          && < 5      }
+
+common attoparsec           { build-depends: attoparsec           >= 0.13       && < 0.14   }
+common bytestring           { build-depends: bytestring           >= 0.10.6     && < 0.11   }
+common hedgehog             { build-depends: hedgehog             >= 1.0        && < 1.1    }
+common hspec                { build-depends: hspec                >= 2.4        && < 3      }
+common hw-hspec-hedgehog    { build-depends: hw-hspec-hedgehog    >= 0.1.0.4    && < 0.2    }
+common hw-prim              { build-depends: hw-prim              >= 0.6.2.21   && < 0.7    }
+common text                 { build-depends: text                 >= 1.2        && < 1.3    }
+
+common config
+  default-language: Haskell2010
+  ghc-options:      -Wall
+
+library
+  import:   base, config
+          , attoparsec
+          , bytestring
+          , hw-prim
+          , text
+  hs-source-dirs:       src
+  exposed-modules:      HaskellWorks.Data.Parser
+  other-modules:        Paths_hw_parser
+  autogen-modules:      Paths_hw_parser
+
+test-suite hw-parser-test
+  import:   base, config
+          , hedgehog
+          , hspec
+          , hw-hspec-hedgehog
+  type:                 exitcode-stdio-1.0
+  main-is:              Spec.hs
+  build-depends:        hw-parser
+  hs-source-dirs:       test
+  ghc-options:          -threaded -rtsopts -with-rtsopts=-N
+  build-tool-depends:   hspec-discover:hspec-discover
+  other-modules:        Paths_hw_parser
+  autogen-modules:      Paths_hw_parser
diff --git a/src/HaskellWorks/Data/Parser.hs b/src/HaskellWorks/Data/Parser.hs
--- a/src/HaskellWorks/Data/Parser.hs
+++ b/src/HaskellWorks/Data/Parser.hs
@@ -1,19 +1,23 @@
+{-# LANGUAGE FunctionalDependencies #-}
+{-# LANGUAGE MultiParamTypeClasses  #-}
+
 module HaskellWorks.Data.Parser
   ( Parser(..)
   ) where
 
-import qualified Data.Attoparsec.ByteString                as ABS
-import qualified Data.Attoparsec.ByteString.Char8          as BC
-import qualified Data.Attoparsec.Text                      as AT
-import qualified Data.Attoparsec.Types                     as T
-import           Data.ByteString                           (ByteString)
-import           Data.MonoTraversable
-import           Data.Text                                 (Text)
-import           HaskellWorks.Data.Char.IsChar
+import Data.ByteString               (ByteString)
+import Data.Text                     (Text)
+import Data.Word
+import HaskellWorks.Data.Char.IsChar
 
-class MonoTraversable t => Parser t where
-  satisfy :: (Element t -> Bool) -> T.Parser t (Element t)
-  satisfyWith :: (Element t -> a) -> (a -> Bool) -> T.Parser t a
+import qualified Data.Attoparsec.ByteString       as ABS
+import qualified Data.Attoparsec.ByteString.Char8 as BC
+import qualified Data.Attoparsec.Text             as AT
+import qualified Data.Attoparsec.Types            as T
+
+class Parser t e | t -> e where
+  satisfy :: (e -> Bool) -> T.Parser t e
+  satisfyWith :: (e -> a) -> (a -> Bool) -> T.Parser t a
   satisfyChar :: (Char -> Bool) -> T.Parser t Char
   string :: t -> T.Parser t t
   try :: T.Parser t a -> T.Parser t a
@@ -21,7 +25,7 @@
   (<?>) :: T.Parser t Char -> String -> T.Parser t Char
   rational :: Fractional f => T.Parser t f
 
-instance Parser ByteString where
+instance Parser ByteString Word8 where
   satisfy = ABS.satisfy
   satisfyWith = ABS.satisfyWith
   satisfyChar = ABS.satisfyWith toChar
@@ -39,7 +43,7 @@
   {-# INLINE (<?>)       #-}
   {-# INLINE rational    #-}
 
-instance Parser Text where
+instance Parser Text Char where
   satisfy = AT.satisfy
   satisfyWith = AT.satisfyWith
   satisfyChar = AT.satisfyWith toChar
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}