systemd unit with Restart=always RestartSec=30 is enough for 99% of the small apps If you can get away with VPS(es) and cloud hosted DB that will be

systemd unit with Restart=always RestartSec=30 is enough for 99% of the small apps If you can get away with VPS(es) and cloud hosted DB that will be by far the simplest solution to manage. Or "serverless" if service is small enough and doesn't need to be persistently running. Once it starts bringing actual money you might then start thinking about dockers, k8s and other fancy stuff