# Pastebin 5tL5O9MT
diff --git a/Main.hs b/Main.hs
index d973c8d..ce8dbb6 100644
--- a/Main.hs
+++ b/Main.hs
@@ -7,6 +7,11 @@
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TemplateHaskell     #-}
 {-# LANGUAGE TypeOperators       #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
 
 module Main where
 
@@ -16,6 +21,9 @@ import           Polysemy.Error
 import qualified Control.Monad.Error as E
 import qualified Control.Monad.Reader as R
 
+import qualified Control.Monad.Freer.Error as FE
+import qualified Control.Monad.Freer as F
+
 {- ############# polysemy ################ -}
 
 data Resource (m :: * -> *) a where
@@ -36,13 +44,40 @@ result = run $ runError $ runErroringInt $ program
 
 {- ######### MTL ########### -}
 
-program2 :: (E.MonadError String m, R.MonadReader Int m) => m Int
-program2 = do
-  R.ask `E.catchError` const (pure 1)
+class MonadResource m where
+  getInt' ::  m Int
+
+program2 :: (E.MonadError String m, MonadResource m) => m Int
+program2 = getInt' `E.catchError` const (pure 1)
+
+newtype ResourceT m a = ResourceT { runResourceT :: m a }
+  deriving (Functor, Applicative, Monad)
+
+deriving instance E.MonadError e m => E.MonadError e (ResourceT m)
+
+instance E.MonadError String m => MonadResource (ResourceT m) where
+  getInt' = ResourceT $ E.throwError "foo"
 
 result2 :: Either String Int
-result2 = R.runReaderT program2 (error "error")
-{- Right *** Exception: error -}
+result2 = runResourceT program2
+{- Right 1 -}
+
+{- ######### Free ########### -}
+
+data ResourceF a where
+  GetInt' :: ResourceF Int
+
+getInt'' :: F.Member ResourceF effs => F.Eff effs Int
+getInt'' = F.send GetInt'
+
+program3 :: (F.Member ResourceF effs, F.Member (FE.Error String) effs) => F.Eff effs Int
+program3 = getInt'' `FE.catchError` \(_ :: String) -> pure 1
+
+runErroringInt' :: F.Member (FE.Error String) effs => F.Eff (ResourceF ': effs) a -> F.Eff effs a
+runErroringInt' = F.interpret $ \GetInt' -> FE.throwError "bar"
+
+result3 :: Either String Int
+result3 = F.run $ FE.runError $ runErroringInt' program3
 
 main :: IO ()
 main = undefined
diff --git a/poly.cabal b/poly.cabal
index 7ae9941..582396e 100644
--- a/poly.cabal
+++ b/poly.cabal
@@ -19,4 +19,5 @@ executable poly
                      , polysemy
                      , polysemy-plugin
                      , mtl
+                     , freer-simple
   ghc-options:         -fplugin=Polysemy.Plugin