diff --git a/CLI/Gif.hs b/CLI/Gif.hs
index bed80ba..fc30601 100644
--- a/CLI/Gif.hs
+++ b/CLI/Gif.hs
@@ -2,6 +2,7 @@
 
 module CLI.Gif where
 
+import qualified Data.ByteString.Char8 as B
 import Diagrams.Backend.Cairo.CmdLine
 import Graphics.Diagram.Gif
 import MyPrelude
@@ -9,5 +10,5 @@ import MyPrelude
 
 gifCLI :: FilePath -> IO ()
 gifCLI _ = do
-  mesh <- readFile "UB1_sonderfaelle.obj"
+  mesh <- B.readFile "UB1_sonderfaelle.obj"
   gifMain (gifDiagS def mesh)
diff --git a/GUI/Gtk.hs b/GUI/Gtk.hs
index ad6f7e7..0262241 100644
--- a/GUI/Gtk.hs
+++ b/GUI/Gtk.hs
@@ -5,6 +5,7 @@ module GUI.Gtk (makeGUI) where
 import Control.Applicative
 import Control.Monad(unless)
 import Control.Monad.IO.Class
+import qualified Data.ByteString.Char8 as B
 import Diagrams.Prelude
 import Diagrams.Backend.Cairo
 import Diagrams.Backend.Cairo.Internal
@@ -235,7 +236,7 @@ saveAndDrawDiag :: FilePath -- ^ obj file to parse
 saveAndDrawDiag fp fps mygui =
   if (==) ".obj" . takeExtension $ fp
     then do
-      mesh            <- readFile fp
+      mesh            <- B.readFile fp
       mainDrawWindow  <- widgetGetDrawWindow (mainDraw mygui)
       treeDrawWindow  <- widgetGetDrawWindow (treeDraw mygui)
       adjustment      <- rangeGetAdjustment (ptScale mygui)
diff --git a/Graphics/Diagram/Gif.hs b/Graphics/Diagram/Gif.hs
index 454e6f4..765bc1d 100644
--- a/Graphics/Diagram/Gif.hs
+++ b/Graphics/Diagram/Gif.hs
@@ -5,6 +5,7 @@ module Graphics.Diagram.Gif where
 import Algebra.VectorTypes
 import Algorithms.ConvexHull.GrahamScan
 import Codec.Picture.Gif
+import qualified Data.ByteString.Char8 as B
 import Data.Monoid
 import Diagrams.Backend.Cairo
 import Diagrams.Prelude hiding ((<>))
@@ -33,5 +34,5 @@ gifDiag p xs =
 
 -- |Same as gifDiag, except that it takes a string containing the
 -- mesh file content instead of the the points.
-gifDiagS :: DiagProp -> MeshString -> [(Diagram Cairo R2, GifDelay)]
+gifDiagS :: DiagProp -> B.ByteString -> [(Diagram Cairo R2, GifDelay)]
 gifDiagS p = gifDiag p . filterValidPT p . meshToArr
diff --git a/Graphics/Diagram/Gtk.hs b/Graphics/Diagram/Gtk.hs
index 51f4114..773601f 100644
--- a/Graphics/Diagram/Gtk.hs
+++ b/Graphics/Diagram/Gtk.hs
@@ -2,6 +2,7 @@
 
 module Graphics.Diagram.Gtk where
 
+import qualified Data.ByteString.Char8 as B
 import Diagrams.Backend.Cairo
 import Diagrams.Prelude
 import Graphics.Diagram.Plotter
@@ -36,7 +37,7 @@ diag p objs@(Objects _)
 
 -- |Create the Diagram from a String which is supposed to be the contents
 -- of an obj file.
-diagS :: DiagProp -> MeshString -> Diagram Cairo R2
+diagS :: DiagProp -> B.ByteString -> Diagram Cairo R2
 diagS p mesh
   | algo p == 2 || algo p == 3 =
       diag p
@@ -49,7 +50,7 @@ diagS p mesh
 
 -- |Create the tree diagram from a String which is supposed to be the contents
 -- of an obj file.
-diagTreeS :: DiagProp -> MeshString -> Diagram Cairo R2
+diagTreeS :: DiagProp -> B.ByteString -> Diagram Cairo R2
 diagTreeS p mesh
   | algo p == 4 = mkDiag treePretty p (Object
                                        . filterValidPT p
diff --git a/Parser/Meshparser.hs b/Parser/Meshparser.hs
index 17174f9..52431c1 100644
--- a/Parser/Meshparser.hs
+++ b/Parser/Meshparser.hs
@@ -12,24 +12,23 @@ import Diagrams.TwoD.Types
 
 -- |Convert a text String with multiple vertices and faces into
 -- a list of vertices, ordered by the faces specification.
-facesToArr :: String -> [[PT]]
+facesToArr :: B.ByteString -> [[PT]]
 facesToArr str = fmap (fmap (\y -> meshs str !! (fromIntegral y - 1)))
                       (faces str)
   where
     meshs = meshToArr
-    faces = rights . fmap (parseOnly parseFace) . B.lines . B.pack
+    faces = rights . fmap (parseOnly parseFace) . B.lines
 
 
 -- |Convert a text String with multiple vertices into
 -- an array of float tuples.
-meshToArr :: String   -- ^ the string to convert
-          -> [PT]     -- ^ the resulting vertice table
+meshToArr :: B.ByteString -- ^ the string to convert
+          -> [PT]         -- ^ the resulting vertice table
 meshToArr =
   fmap p2
     . rights
     . fmap (parseOnly parseVertice)
     . B.lines
-    . B.pack
 
 
 -- |Creates a Parser that accepts a single vertice, such as 'v 1.0 2.0'.