bracket

set ➜  ~  ./test2 &
[1] 22997
set ➜  ~  kill 22997
[1]  + 22997 terminated  ./test2                                                                                                                            
set ➜  ~  cat test2.hs
import Control.Exception
import Control.Concurrent

main :: IO ()
main = bracket (return ()) (\_ -> putStrLn "come to collect") (\_ -> threadDelay  30000000)
set ➜  ~