The moment you do this, you forego one of the biggest advantages of using heroku. As long as you're on heroku only, you don't need to take care of securing the underlying stack - that is firewall rules, OS-updates, general maintenance. The moment you spin up a single AWS instance besides it, it's your problem. Depending on your use-case it could be a better choice to just go all the way to dedicated hardware: The primary advantage AWS has over dedicated hardware is flexibility. You can spin up instances depending on your current need. If your load behavior is a flat, predictable curve you might just not need that - and then real hardware is cheaper in most cases.