diff --git a/Data/Vector/Algorithms/AmericanFlag.hs b/Data/Vector/Algorithms/AmericanFlag.hs
--- a/Data/Vector/Algorithms/AmericanFlag.hs
+++ b/Data/Vector/Algorithms/AmericanFlag.hs
@@ -27,6 +27,8 @@
 import Data.Int
 import Data.Bits
 
+import qualified Data.ByteString as B
+
 import Data.Vector.Generic.Mutable
 import qualified Data.Vector.Primitive.Mutable as PV
 
@@ -163,6 +165,16 @@
   index 6 n = (n `shiftR`  8) .&. 255
   index 7 n = n .&. 255
   index _ _ = 0
+  {-# INLINE index #-}
+
+instance Lexicographic B.ByteString where
+  terminate b i = i >= B.length b
+  {-# INLINE terminate #-}
+  size _ = 257
+  {-# INLINE size #-}
+  index i b
+    | i >= B.length b = 0
+    | otherwise       = fromIntegral (B.index b i) + 1
   {-# INLINE index #-}
 
 sort :: forall e m v. (PrimMonad m, MVector v e, Lexicographic e, Ord e)
diff --git a/tests/Tests.hs b/tests/Tests.hs
--- a/tests/Tests.hs
+++ b/tests/Tests.hs
@@ -14,6 +14,8 @@
 import Data.Int
 import Data.Word
 
+import qualified Data.ByteString as B
+
 import Data.Vector (Vector)
 import qualified Data.Vector as V
 
@@ -88,7 +90,7 @@
   qc (label "flag Int32"       . prop_fullsort (AF.sort :: Algo Int32  ()))
   qc (label "flag Int64"       . prop_fullsort (AF.sort :: Algo Int64  ()))
   qc (label "flag Int"         . prop_fullsort (AF.sort :: Algo Int    ()))
---  qc (label "flag (Int, Int)"  . prop_fullsort (R.sort :: Algo (Int, Int) ()))
+  qc (label "flag ByteString"  . prop_fullsort (AF.sort :: Algo B.ByteString ()))
  where
  qc algo = quickCheckWith args algo
 
@@ -141,6 +143,7 @@
   qc $ label "flag W32"     . prop_permutation (AF.sort :: Algo Word32 ())
   qc $ label "flag W64"     . prop_permutation (AF.sort :: Algo Word64 ())
   qc $ label "flag Word"    . prop_permutation (AF.sort :: Algo Word   ())
+  qc $ label "flag ByteString" . prop_permutation (AF.sort :: Algo B.ByteString ())
  where
  qc prop = quickCheckWith args prop
 
diff --git a/tests/Util.hs b/tests/Util.hs
--- a/tests/Util.hs
+++ b/tests/Util.hs
@@ -8,6 +8,8 @@
 import Data.Word
 import Data.Int
 
+import qualified Data.ByteString as B
+
 import qualified Data.Vector as V
 
 import Data.Vector.Mutable hiding (length)
@@ -25,4 +27,7 @@
 
 instance (Arbitrary e) => Arbitrary (V.Vector e) where
   arbitrary = fmap V.fromList arbitrary
+
+instance Arbitrary B.ByteString where
+  arbitrary = B.pack `fmap` arbitrary
 
diff --git a/vector-algorithms.cabal b/vector-algorithms.cabal
--- a/vector-algorithms.cabal
+++ b/vector-algorithms.cabal
@@ -1,5 +1,5 @@
 Name:              vector-algorithms
-Version:           0.5.0
+Version:           0.5.1
 License:           BSD3
 License-File:      LICENSE
 Author:            Dan Doel
@@ -26,7 +26,10 @@
   Default: False
 
 Library
-    Build-Depends: base >= 3 && < 5, vector >= 0.6 && < 0.8, primitive >=0.3 && <0.4
+    Build-Depends: base >= 3 && < 5,
+                   vector >= 0.6 && < 0.8,
+                   primitive >=0.3 && <0.4,
+                   bytestring >= 0.9 && < 0.10
 
     Exposed-Modules:
         Data.Vector.Algorithms.Optimal