Simple Web App in Haskell

Main.hs

import Blaze.ByteString.Builder (fromByteString)
import Data.CaseInsensitive (mk)
import qualified Data.ByteString.Char8 as C8
import qualified Data.ByteString.UTF8 as U8
import Network.HTTP.Types
import Network.Wai
import Network.Wai.Handler.Warp (run)

myApp :: Application
myApp _ = do
  return $ ResponseBuilder status headers body
    where
      status  = statusOK
      headers = [(mk $ C8.pack "Content-Type", C8.pack "text/plain; charset=utf-8")]
      body    = fromByteString $ U8.fromString "Hello, 世界!"

main :: IO ()
main = run port myApp
  where
    port = 8080