This works, but am I doing it right?

scottydb.hs

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE DeriveGeneric #-}

module Main where

--import Web.Scotty
import Web.Scotty.Trans
import Data.Aeson (FromJSON, ToJSON)
import Data.Text.Lazy (Text)
import Data.Monoid ((<>))
import GHC.Generics
import Control.Applicative
import Control.Monad.Reader
import Database.SQLite.Simple
import Database.SQLite.Simple.FromRow

data User = User { userId :: Int, userName :: String } deriving (Show, Generic)

instance FromRow User where
  fromRow = User <$> field <*> field

instance ToRow User where
  toRow (User id_ name_) = toRow (id_, name_)

instance ToJSON User
instance FromJSON User

type ScottyD = ScottyT Text (ReaderT (Connection) IO)

saveUser :: IO ()
saveUser = do
  conn <- open "test.db"
  execute conn "insert into users (userId, userName) values (?, ?)"
    (User {userId = 3, userName = "some guy"})
  close conn

getUser :: Connection -> Int -> IO [User]
getUser conn id = do
  query_ conn "select * from users" :: IO [User]

matchesId :: Int -> User -> Bool
matchesId id user = userId user == id

routes :: ScottyD ()
routes = do
  get "/hello" $ do
    text "hello world"
  get "/people/:id" $ do
    id <- param "id"
    conn <- lift ask
    users <- liftIO $ getUser conn id
    json (filter (matchesId id) users)
  get "/people" $ do
    conn <- lift ask
    users <- liftIO $ getUser conn 0
    json users

main :: IO ()
main = do
  putStr "Starting server..."
  conn <- open "test.db"
  let read = \r -> runReaderT r conn  -- stuff the Connection into Reader
  scottyT 3000 read routes
  close conn