On the Symfony Finland site there's a tutorial posted showing you how to run Symfony without a web server using Docker and PHP-PM.
Docker containers have been becoming an increasingly common deployment method in the past few years. I've deployed some Node.js app in containers, which are very simple to deploy as there's a single process that's easy to run. I found running PHP to be more complex.
[...] When running Nginx and PHP-FPM you are forced to run a pair of of containers, one for PHP-FPM and one for PHP-NPM. [...] But I would rather just run a single process to run the application. This is how Go, Node.js and even .NET Core apps are deployed. Can PHP do without a middle man?
While it may not be the most performant way to run a PHP and Symfony application, the author wanted to try it out and see how difficult it might be. The code for the setup is provided and, while the end result was a bit difficult to get to, it was possible.