Help debugging the pantry lock bug

Main.hs

import RIO
import Pantry
import Path

data App = App SimpleApp PantryConfig
instance HasPantryConfig App where
  pantryConfigL = lens (\(App _ pc) -> pc) undefined
instance HasLogFunc App where
  logFuncL = (lens (\(App sa _) -> sa) undefined).logFuncL

main :: IO ()
main = runSimpleApp $ do
  dir <- parseAbsDir "/Users/michael/Desktop/pantry-test"
  withPantryConfig dir defaultHackageSecurityConfig HpackBundled 3 $ \pc -> do
    env <- ask
    runRIO (App env pc) $ replicateConcurrently_ 10 $ updateHackageIndex Nothing

run.sh

#!/usr/bin/env bash

set -euxo pipefail

ghc Main.hs -threaded -fforce-recomp
./Main&
./Main&
./Main&
./Main&
./Main&