diff --git a/geo-uk.cabal b/geo-uk.cabal
--- a/geo-uk.cabal
+++ b/geo-uk.cabal
@@ -1,8 +1,5 @@
--- Initial geo-uk.cabal generated by cabal init.  For further 
--- documentation, see http://haskell.org/cabal/users-guide/
-
 name:                geo-uk
-version:             0.1.0.1
+version:             0.1.0.2
 synopsis:            High precision conversion between GPS and UK Grid
 description:         Conversion between GPS and UKGrid Coordinates one approximate and one using table.
 homepage:            https://github.com/tolysz/geo-uk
@@ -16,6 +13,9 @@
 extra-source-files:  data/GB.dat
 cabal-version:       >=1.10
 
+data-files:
+   data/GB.dat
+
 Flag embeded
   Description:   Embed Static data
   Default:       False
@@ -24,18 +24,17 @@
   exposed-modules:     Data.Geo.OSGM02Tab
                        Data.Geo.Type
                        Data.Geo.Point
-  -- other-modules:       
-  -- other-extensions:
   if flag(embeded)
       cpp-options: -DEMBEDED_DATA
-      build-depends: bzlib
-                   , file-embed
-  build-depends:       base >=4.7 && < 5
-               ,       array
-               ,       binary
-               ,       bytestring
-               ,       th-lift
-               ,       template-haskell
+      build-depends: file-embed
+
+  build-depends: base >=4.7 && < 5
+               , array
+               , binary
+               , bytestring
+               , th-lift
+               , template-haskell
+               , bzlib
   hs-source-dirs:      src
   default-language:    Haskell2010
-  ghc-options: -O2
+
diff --git a/src/Data/Geo/OSGM02Tab.hs b/src/Data/Geo/OSGM02Tab.hs
--- a/src/Data/Geo/OSGM02Tab.hs
+++ b/src/Data/Geo/OSGM02Tab.hs
@@ -9,22 +9,26 @@
 import Data.Maybe
 import Data.Geo.Type
 import Data.Array.Unboxed ((!))
-
-#if EMBEDED_DATA
 import qualified Codec.Compression.BZip as BZip
 import qualified Data.ByteString.Lazy.Char8 as L8
 import Data.Binary (decode)
-import Data.FileEmbed
-import qualified Data.ByteString
-
-gb :: Maybe ArrDD
-gb = Just (decodePTPDDFile . L8.fromStrict $ $(embedFile "data/GB.dat"))
+-- import qualified Data.ByteString
 
-decodePTPDDFile :: L8.ByteString -> ArrDD
-decodePTPDDFile = decode . BZip.decompress
+#if EMBEDED_DATA
+import Data.FileEmbed
 
+gb :: ArrDD
+gb = decodePTPDDFile . L8.fromStrict $ $(embedFile "data/GB.dat")
 #else
-gb :: Maybe ArrDD
-gb = Nothing
+import System.IO.Unsafe
+import Paths_geo_uk
+
+{-# NOINLINE gb #-}
+gb :: ArrDD
+gb = unsafePerformIO $ do
+  fn <- getDataFileName "data/GB.dat"
+  decodePTPDDFile <$> L8.readFile fn
 #endif
 
+decodePTPDDFile :: L8.ByteString -> ArrDD
+decodePTPDDFile = decode . BZip.decompress
diff --git a/src/Data/Geo/Point.hs b/src/Data/Geo/Point.hs
--- a/src/Data/Geo/Point.hs
+++ b/src/Data/Geo/Point.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE EmptyDataDecls #-}
+-- {-# LANGUAGE EmptyDataDecls #-}
 
 module Data.Geo.Point
 (
@@ -110,17 +110,14 @@
     no = i +  mlam2 * (ii + mlam2 * (iii + iiia * mlam2))
 
 convWGS84ENtoUKOS :: WGS84EN -> UKOS
-convWGS84ENtoUKOS pt@(WGS84EN we wn wa) =
-   case gb of
-   Just gb' -> UKOS  e n h
+convWGS84ENtoUKOS pt@(WGS84EN we wn wa) = UKOS  e n h
        where
          ei  = round (we / 1000)
          ni  = round (wn / 1000)
-         Just gb' = gb
-         (PTPDD se0 sn0 sg0 ) = gb' ! (ei,ni)
-         (PTPDD se1 sn1 sg1 ) = gb' ! (ei+1,ni)
-         (PTPDD se2 sn2 sg2 ) = gb' ! (ei+1,ni+1)
-         (PTPDD se3 sn3 sg3 ) = gb' ! (ei,ni+1)
+         (PTPDD se0 sn0 sg0 ) = gb ! (ei,ni)
+         (PTPDD se1 sn1 sg1 ) = gb ! (ei+1,ni)
+         (PTPDD se2 sn2 sg2 ) = gb ! (ei+1,ni+1)
+         (PTPDD se3 sn3 sg3 ) = gb ! (ei,ni+1)
          dx = we - 1000 * fromIntegral ei
          dy = wn - 1000 * fromIntegral ni
          t = dx / 1000
@@ -131,8 +128,6 @@
          e = we + se
          n = wn + sn
          h = wa - sg
-   Nothing -> convWGS84ENtoUKOS' pt
-
 
 convGPStoSHORT = convUKOStoSHORT . convGPStoUKOS
 convGPStoSHORT' = convUKOStoSHORT . convGPStoUKOS'