gistfile1.txt

src/Main.hs:39:20:
    No instance for (MonadReader
                       MyEnv (ActionT TL.Text (ReaderT MyEnv IO)))
      arising from the 'deriving' clause of a data type declaration
    Possible fix:
      add an instance declaration for
      (MonadReader MyEnv (ActionT TL.Text (ReaderT MyEnv IO)))
      or use a standalone 'deriving instance' declaration,
           so you can specify the instance context yourself
    When deriving the instance for (MonadReader MyEnv MyMonad)

reader.hs

data MyEnv = MyEnv{abcd :: T.Text}
newtype MyMonad a = MyMonad (ActionT TL.Text (ReaderT MyEnv IO) a)
  deriving (Monad, MonadReader MyEnv)