diff --git a/apps/Dump.hs b/apps/Dump.hs
--- a/apps/Dump.hs
+++ b/apps/Dump.hs
@@ -10,6 +10,7 @@
 import qualified Data.ByteString.Lazy.Char8 as BSL8
 import qualified Data.ByteString.Lazy as BSL
 import qualified Data.ByteString.Lazy.Builder as Builder
+import qualified Data.ByteString.Lazy.Builder.ASCII as ASCIIBuilder
 import           Data.Function (fix)
 import           Data.IORef
 import           Data.List
@@ -117,7 +118,7 @@
 whitespaceFormat :: EmotivState -> BSL.ByteString
 whitespaceFormat EmotivState{ counter, battery, gyroX, gyroY, sensors, qualities }
   = Builder.toLazyByteString . mconcat
-    . intersperse (Builder.char8 ' ') . map Builder.intDec $ ints
+    . intersperse (Builder.char8 ' ') . map ASCIIBuilder.intDec $ ints
   where
     ints = [ counter, battery, gyroX, gyroY ] ++ V.toList sensors ++ V.toList qualities
 
diff --git a/apps/DumpConduit.hs b/apps/DumpConduit.hs
--- a/apps/DumpConduit.hs
+++ b/apps/DumpConduit.hs
@@ -11,6 +11,7 @@
 import qualified Data.ByteString.Lazy as BSL
 import qualified Data.ByteString.Lazy.Char8 as BSL8
 import qualified Data.ByteString.Lazy.Builder as Builder
+import qualified Data.ByteString.Lazy.Builder.ASCII as ASCIIBuilder
 import           Data.Conduit
 import qualified Data.Conduit.List as CL
 import           Data.Function (fix)
@@ -118,7 +119,7 @@
 whitespaceFormat :: EmotivState -> BSL.ByteString
 whitespaceFormat EmotivState{ counter, battery, gyroX, gyroY, sensors, qualities }
   = Builder.toLazyByteString . mconcat
-    . intersperse (Builder.char8 ' ') . map Builder.intDec $ ints
+    . intersperse (Builder.char8 ' ') . map ASCIIBuilder.intDec $ ints
   where
     ints = [ counter, battery, gyroX, gyroY ] ++ V.toList sensors ++ V.toList qualities
 
diff --git a/hemokit.cabal b/hemokit.cabal
--- a/hemokit.cabal
+++ b/hemokit.cabal
@@ -1,5 +1,5 @@
 name:          hemokit
-version:       0.6.1
+version:       0.6.2
 license:       MIT
 copyright:     2013 Niklas Hambüchen <mail@nh2.me>, Patrick Chilton <chpatrick@gmail.com>
 author:        Niklas Hambüchen <mail@nh2.me>, Patrick Chilton <chpatrick@gmail.com>