how can I make my app to run always and not pause or shutdown

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how can I make my app to run always and not pause or shutdown

2

Have you seen the documentation about auto start/stop machines?
Ref: Automatically Stop and Start Machines · Fly Docs

I’ve recently run into it and set my apps with:

  auto_stop_machines = false
  auto_start_machines = false

Just keep in mind that this will cost you extra money!