Hi Andy, Your program didn't compile as given, so I cut out some of the event handling fanciness you were doing. Also, my modified version restarts whenever the 'r' key is pressed. I figure those changes aren't important to the problem at hand. Anyway, I don't think it's ever going to be possible to define a Binary instance for a TextView, since all of the functions which can yield information about it are impure. I would recommend extracting the relevant data beforehand, and then persisting it in a tuple. You could use some 'marshal<WIDGET>' and 'recreate<WIDGET>' functions if you need to persist many different widget types. Saving just the text can be done as follows: <code> module DyreExample where import Graphics.UI.Gtk hiding (get) import qualified Graphics.UI.Gtk.Gdk.Events as E import qualified Config.Dyre as Dyre import Config.Dyre.Relaunch import System.IO import Data.Binary data Config = Config { message :: String, errorMsg :: Maybe String } defaultConfig :: Config defaultConfig = Config "Dyre Example v0.1" Nothing showError :: Config -> String -> Config showError cfg msg = cfg { errorMsg = Just msg } realMain Config{message = message, errorMsg = errorMsg } = do initGUI textView <- textViewNew textBuffer <- textViewGetBuffer textView text <- restoreBinaryState "" putStrLn $ "Restored state: " ++ text textBufferSetText textBuffer text rootWindow <- windowNew rootWindow `onDestroy` mainQuit windowFullscreen rootWindow rootWindow `containerAdd` textView widgetShowAll rootWindow rootWindow `onKeyPress` (\event -> dyreKeyTest event textView) mainGUI dyreExample = Dyre.wrapMain $ Dyre.defaultParams { Dyre.projectName = "Main" , Dyre.realMain = realMain , Dyre.showError = showError } dyreKeyTest :: E.Event -> TextView -> IO Bool dyreKeyTest ev textView = do case E.eventKeyName ev of "r" -> do textBuffer <- textViewGetBuffer textView sI <- textBufferGetStartIter textBuffer eI <- textBufferGetEndIter textBuffer text <- textBufferGetText textBuffer sI eI True putStrLn $ "Relaunching with state: " ++ text relaunchWithBinaryState text Nothing return True _ -> return False </code> Other comments: 1. It isn't necessary to explicitly tell Dyre to do a custom compile. It will take care of figuring that out once you restart it. 2. Instead of manually setting paths in the code, you can use the '--dyre-debug' command-line flag, which will cause Dyre to look for configurations in the current directory, and store temporary files in a 'cache' subdirectory. 3. Giving a project name of 'Main' causes Dyre to see the file 'Main.hs' as a custom configuration. I'm not sure if that's what you intended, but it will make testing custom configurations harder than it needs to be. 4. Good luck with the rest of your project! - Will Donnelly