I deeply disagree. Docker’s key innovation is not its isolation; it’s the packaging. There is no other language-agnostic way to say “here’s code, run it on the internet”. Solutions prior to Docker (eg buildpacks) were not so much language agnostic as they were language aware.
Even if you allow yourself the disadvantage that any non-Docker solution won’t be language-agnostic: how do you get the code bundle to your server? Zip & SFTP? How do you start it? ./start.sh? How do you restart under failure? Systemd? Congrats, you reinvented docker but worse. Want to upgrade a dependency due to a security vulnerability? Do you want to SSH into N replicated VMs and run your Linux distribution specific package update command, or press the little refresh icon in your CI to rebuild a new image then be done?
Docker is the one good thing the ops industry has invented in the last 15 years.
Even if you allow yourself the disadvantage that any non-Docker solution won’t be language-agnostic: how do you get the code bundle to your server? Zip & SFTP? How do you start it? ./start.sh? How do you restart under failure? Systemd? Congrats, you reinvented docker but worse. Want to upgrade a dependency due to a security vulnerability? Do you want to SSH into N replicated VMs and run your Linux distribution specific package update command, or press the little refresh icon in your CI to rebuild a new image then be done?
Docker is the one good thing the ops industry has invented in the last 15 years.