diff --git a/Distribution/MacOSX.hs b/Distribution/MacOSX.hs
--- a/Distribution/MacOSX.hs
+++ b/Distribution/MacOSX.hs
@@ -16,6 +16,7 @@
 
 module Distribution.MacOSX (
   appBundleBuildHook, appBundleInstallHook,
+  makeAppBundle,
   MacApp(..),
   ChaseDeps(..),
   Exclusions,
@@ -40,6 +41,7 @@
 import System.Directory (copyFile, createDirectoryIfMissing)
 import System.Exit
 
+import Distribution.MacOSX.AppBuildInfo
 import Distribution.MacOSX.Common
 import Distribution.MacOSX.Dependencies
 
@@ -54,7 +56,7 @@
   -> BuildFlags -> PackageDescription -> LocalBuildInfo -> IO ()
 appBundleBuildHook apps _ _ pkg localb =
   if isMacOS
-     then forM_ apps' $ makeAppBundle localb
+     then forM_ apps' $ makeAppBundle . toAppBuildInfo localb
      else putStrLn "Not OS X, so not building an application bundle."
   where apps' = case apps of
                       [] -> map mkDefault $ executables pkg
@@ -76,7 +78,8 @@
   let verbosity = fromFlagOrDefault normal (installVerbosity iflags)
   createDirectoryIfMissing False applicationsDir
   forM_ apps $ \app -> do
-    let appPathSrc = getAppPath localb app
+    let appInfo    = toAppBuildInfo localb app
+        appPathSrc = appPath appInfo
         appPathTgt = applicationsDir </> takeFileName appPathSrc
         exe ap = ap </> pathInApp app (appName app)
     installDirectoryContents verbosity appPathSrc appPathTgt
@@ -99,11 +102,10 @@
 isMacOS = os == "darwin"
 
 -- | Given a 'MacApp' in context, make an application bundle in the
--- build area.
-makeAppBundle ::
-  LocalBuildInfo -> MacApp -> IO ()
-makeAppBundle localb app =
-  do appPath <- createAppDir localb app
+-- build area. (for internal use only)
+makeAppBundle :: AppBuildInfo -> IO ()
+makeAppBundle appInfo@(AppBuildInfo appPath _ app) =
+  do createAppDir appInfo
      maybeCopyPlist appPath app
      maybeCopyIcon appPath app
        `catch` \err -> putStrLn ("Warning: could not set up icon for " ++
@@ -115,8 +117,8 @@
 -- | Create application bundle directory structure in build directory
 -- and copy executable into it.  Returns path to newly created
 -- directory.
-createAppDir :: LocalBuildInfo -> MacApp -> IO FilePath
-createAppDir localb app =
+createAppDir :: AppBuildInfo -> IO FilePath
+createAppDir (AppBuildInfo appPath exeSrc app) =
   do putStrLn $ "Creating application bundle directory " ++ appPath
      createDirectoryIfMissing False appPath
      createDirectoryIfMissing True  $ takeDirectory exeDest
@@ -124,12 +126,7 @@
      putStrLn $ "Copying executable " ++ appName app ++ " into place"
      copyFile exeSrc exeDest
      return appPath
-  where appPath = getAppPath localb app
-        exeDest = appPath </> pathInApp app (appName app)
-        exeSrc = buildDir localb </> appName app </> appName app
-
-getAppPath :: LocalBuildInfo -> MacApp -> FilePath
-getAppPath localb app = buildDir localb </> appName app <.> "app"
+  where exeDest = appPath </> pathInApp app (appName app)
 
 -- | Include any external resources specified.
 includeResources ::
diff --git a/cabal-macosx.cabal b/cabal-macosx.cabal
--- a/cabal-macosx.cabal
+++ b/cabal-macosx.cabal
@@ -1,5 +1,5 @@
 Name:                   cabal-macosx
-Version:                0.1.2.1
+Version:                0.1.2.2
 Stability:              Alpha
 Synopsis:               Cabal support for creating Mac OSX application bundles.
 Description:
@@ -39,3 +39,9 @@
                    Distribution.MacOSX.Dependencies,
                    Distribution.MacOSX.DG
   ghc-options:     -fwarn-tabs -Wall
+
+Executable macosx-app
+  Main-is:         macosx-app.hs
+  Build-Depends:   base >= 4 && < 5, Cabal >= 1.6, directory
+               ,   fgl >= 5.4.2.2 && < 5.5
+               ,   filepath, MissingH, parsec, process
diff --git a/macosx-app.hs b/macosx-app.hs
new file mode 100644
--- /dev/null
+++ b/macosx-app.hs
@@ -0,0 +1,29 @@
+module Main where
+
+import Distribution.MacOSX
+import Distribution.MacOSX.AppBuildInfo
+import System.Directory
+import System.Environment
+import System.FilePath
+
+main = do
+  pname <- getProgName
+  xs    <- getArgs
+  exe <- case xs of
+           [x1] -> return x1 
+           _    -> fail $ "Usage: " ++ pname ++ " <exe>"
+  exeExists <- doesFileExist exe
+  let macapp  = MacApp { appName   = takeFileName exe
+                       , appIcon   = Nothing
+                       , appPlist  = Nothing
+                       , resources = []
+                       , otherBins = []
+                       , appDeps   = DoNotChase
+                       } 
+      appInfo = AppBuildInfo { app        = macapp
+                             , appPath    = appName macapp <.> "app"
+                             , appOrigExe = exe
+                             }
+  if exeExists
+     then makeAppBundle appInfo
+     else fail $ exe ++ " does not exist"