diff --git a/Graphics/Blank.hs b/Graphics/Blank.hs
--- a/Graphics/Blank.hs
+++ b/Graphics/Blank.hs
@@ -25,6 +25,9 @@
 import Control.Concurrent
 import Control.Monad.IO.Class (liftIO)
 import Network.Wai.Handler.Warp (run)
+import Network.Wai (Middleware,remoteHost, responseLBS)
+import qualified Network.HTTP.Types as H
+import Network.Socket (SockAddr(..))
 import Web.Scotty as S
 --import Network.Wai.Middleware.RequestLogger -- Used when debugging
 --import Network.Wai.Middleware.Static
@@ -82,6 +85,7 @@
 
    app <- scottyApp $ do
 --        middleware logStdoutDev
+        middleware local_only
 
 --        middleware $ staticRoot $ TS.pack $ (dataDir ++ "/static")
 
@@ -95,7 +99,7 @@
             text (T.pack $ "session = " ++ show uq ++ ";redraw();")
 
         post "/event/:num" $ do
-            header "Cache-Control" "max-age=0, no-cache, private, no-store, must-revalidate"
+            addHeader "Cache-Control" "max-age=0, no-cache, private, no-store, must-revalidate"
             num <- param "num"
 --            liftIO $ print (num :: Int)
             NamedEvent nm event <- jsonData
@@ -111,7 +115,7 @@
                                       json ()
 
         get "/canvas/:num" $ do
-            header "Cache-Control" "max-age=0, no-cache, private, no-store, must-revalidate"
+            addHeader "Cache-Control" "max-age=0, no-cache, private, no-store, must-revalidate"
             -- do something and return a new list of commands to the client
             num <- param "num"
 --            liftIO $ print (num :: Int)
@@ -163,3 +167,15 @@
               return a
       send' other                  cmds = send' (Bind other Return) cmds
 
+
+local_only :: Middleware
+local_only f r = case remoteHost r of
+                   SockAddrInet _  h | h == fromIntegral home
+                                    -> f r
+                   SockAddrUnix _   -> f r
+                   _                ->  return $ responseLBS H.status403
+                                                             [("Content-Type", "text/plain")]
+                                                             "local access only"
+ where
+        home :: Integer
+        home = 127 + (256 * 256 * 256) * 1
diff --git a/blank-canvas.cabal b/blank-canvas.cabal
--- a/blank-canvas.cabal
+++ b/blank-canvas.cabal
@@ -1,5 +1,5 @@
 Name:                blank-canvas
-Version:             0.2.3
+Version:             0.2.3.1
 Synopsis:            HTML5 Canvas Graphics Library
 Description:         A Haskell port of the HTML5 Canvas API.
                      blank-canvas works by providing a web service that
@@ -9,7 +9,7 @@
 License-file:        LICENSE
 Author:              Andy Gill
 Maintainer:          andygill@ku.edu
-Copyright:           Copyright (c) 2012 The University of Kansas
+Copyright:           Copyright (c) 2013 The University of Kansas
 Homepage:            http://ittc.ku.edu/csdl/fpg/Tools/BlankCanvas
 Category:            Graphics
 Build-type:          Simple
@@ -42,13 +42,16 @@
   default-language:    Haskell2010
   build-depends:       base             >= 4.3.1        && < 5,
                        aeson            == 0.6.*,
-                       containers       >  0.5,
-                       scotty           >= 0.4.6,
+                       containers       == 0.5.*,
+                       scotty           == 0.5.*,
+                       wai              == 1.4.*,
+                       http-types       == 0.8.*,
                        text             == 0.11.*,
-                       transformers     >= 0.2.2,
+                       network          == 2.4.*,
+                       transformers     == 0.3.*,
                        wai-extra        == 1.3.*,
                        warp             >= 1.3.1        && < 1.4,
-                       stm              == 2.2.*
+                       stm              >= 2.2		&& < 2.5
 
   GHC-options:  -Wall -fno-warn-orphans