diff --git a/Setup.hs b/Setup.hs
--- a/Setup.hs
+++ b/Setup.hs
@@ -1,2 +1,3 @@
 import Distribution.Simple
+
 main = defaultMain
diff --git a/src/Data/Validity/Text.hs b/src/Data/Validity/Text.hs
--- a/src/Data/Validity/Text.hs
+++ b/src/Data/Validity/Text.hs
@@ -1,19 +1,26 @@
+{-# OPTIONS_GHC -Wno-orphans #-}
+
 module Data.Validity.Text where
 
-import           Data.Validity
+import Data.Validity
 
-import           Data.Text.Internal (Text(..))
 import qualified Data.Text.Array as A
+import Data.Text.Internal (Text(..))
+import qualified Data.Text.Internal.Encoding.Utf16 as E
 
 -- | A text is valid if the internal structure is consistent.
 instance Validity Text where
     isValid (Text arr off len) =
-        let c    = A.unsafeIndex arr off
-        in    (len >= 0)
-           && (off >= 0)
-           -- TODO(syd) also check the length of the byte array if that is
-           -- possible. Like this:
-           -- && (alen == 0 || len == 0 || off < alen)
-           && (len == 0 || c < 0xDC00 || c > 0xDFFF)
-
-
+        let c = A.unsafeIndex arr off
+        in and
+               [ len >= 0
+               , off >= 0
+               , len == 0 || c < 0xDC00 || c > 0xDFFF
+               , let ws = A.toList arr off len -- Checking for failures while decoding the UTFX
+                 in all E.validate1 ws && all (uncurry E.validate2) (tupsOf ws)
+               ]
+      where
+        tupsOf :: [a] -> [(a, a)]
+        tupsOf [] = []
+        tupsOf [_] = []
+        tupsOf (a:b:rs) = (a, b) : tupsOf rs
diff --git a/validity-text.cabal b/validity-text.cabal
--- a/validity-text.cabal
+++ b/validity-text.cabal
@@ -1,26 +1,29 @@
-name:                validity-text
-version:             0.1.0.1
-synopsis:            Validity instances for text
-description:         Please see README.md
-homepage:            https://github.com/NorfairKing/validity#readme
-license:             MIT
-license-file:        LICENSE
-author:              Tom Sydney Kerckhove
-maintainer:          syd.kerckhove@gmail.com
-copyright:           Copyright: (c) 2016 Tom Sydney Kerckhove
-category:            Web
-build-type:          Simple
--- extra-source-files:
-cabal-version:       >=1.10
+name: validity-text
+version: 0.1.1.0
+cabal-version: >=1.10
+build-type: Simple
+license: MIT
+license-file: LICENSE
+copyright: Copyright: (c) 2016 Tom Sydney Kerckhove
+maintainer: syd.kerckhove@gmail.com
+homepage: https://github.com/NorfairKing/validity#readme
+synopsis: Validity instances for text
+description:
+    Please see README.md
+category: Web
+author: Tom Sydney Kerckhove
 
+source-repository head
+    type: git
+    location: https://github.com/NorfairKing/validity
+
 library
-  hs-source-dirs:      src
-  exposed-modules:     Data.Validity.Text
-  build-depends:       base < 5
-                     , validity
-                     , text
-  default-language:    Haskell2010
+    exposed-modules:
+        Data.Validity.Text
+    build-depends:
+        base <5,
+        validity -any,
+        text -any
+    default-language: Haskell2010
+    hs-source-dirs: src
 
-source-repository head
-  type:     git
-  location: https://github.com/NorfairKing/validity