penpot/exporter/scripts/wait-and-start.sh

#!/usr/bin/env bash

set -e

wait_file() {
  local file="$1"; shift
  local wait_seconds="${1:-10}"; shift # 10 seconds as default timeout

  until test $((wait_seconds--)) -eq 0 -o -f "$file" ; do sleep 1; done

  ((++wait_seconds))
}

wait_file "target/app.js" 120 && {
  node target/app.js
}