diff --git a/oi.cabal b/oi.cabal
--- a/oi.cabal
+++ b/oi.cabal
@@ -1,5 +1,5 @@
 Name:			oi
-Version:		0.4.0
+Version:		0.4.0.1
 Category:		Data
 Synopsis:		Library for purely functional lazy interactions with the outer world.
 Description:		This package implements a data structure and operations on it for writing interactive program with no imperative flavor of IO monads.
@@ -20,7 +20,7 @@
   Default-Language:         Haskell2010
   Hs-Source-Dirs:	    src/
   Build-Depends:	    base >= 4.5 && < 5, parallel, comonad >= 3, filepath, directory
-  GHC-Options:		    -O0 -fcase-merge -fcse -fdo-eta-reduction -fenable-rewrite-rules -ffloat-in -ffull-laziness -fspecialise -fstrictness 
+  GHC-Options:		    -fno-cse -fno-full-laziness
   Exposed-modules:	    Data.OI
                           , Data.OI.Internal
                           , Data.OI.Combinator
@@ -45,6 +45,12 @@
                           , oi
   Default-Language:         Haskell2010
                            
+Executable oi-echoc
+  Hs-Source-Dirs:           sample/
+  Main-Is:                  echoc.hs
+  Build-Depends:            base >= 4.5 && < 5
+                          , oi
+  Default-Language:         Haskell2010
 Executable oi-echo
   Hs-Source-Dirs:           sample/
   Main-Is:                  echo.hs
diff --git a/sample/echoc.hs b/sample/echoc.hs
new file mode 100644
--- /dev/null
+++ b/sample/echoc.hs
@@ -0,0 +1,22 @@
+{-# LANGUAGE TypeOperators #-}
+module Main where
+
+import Data.OI hiding (isEOF)
+
+import Data.Bool
+import Data.Maybe
+import System.IO
+
+import qualified System.Environment as Sys (getArgs)
+
+main :: IO ()
+main =  runInteraction pmain
+
+pmain :: (Char, ()) :-> ()
+pmain = getc |/| putc
+
+getc :: Char :-> Char
+getc = iooi (hSetBuffering stdin NoBuffering >> getChar)
+
+putc :: Char -> () :-> ()
+putc = iooi . (\c -> hSetBuffering stdout NoBuffering >> hPutChar stdout c >> hFlush stdout)