We add jsbuilding-rails to get esbuild running in the app, and then we copy-paste the files we need from impress-2020 into here!
I stopped at the point where it was building successfully, but it's not running correctly: it's not sure about `process.env` in `next`, and I think the right next step is to delete the NextJS deps altogether and use React Router instead.
The intent is to set up for an upgrade of Ruby and Rails to the modern versions, but I want to start by having a stable running copy that we can incrementally pull up to new versions of things!
And it turns out getting Ruby 1.9.3 to build on modern platforms is hard! I started by trying on macOS and just couldn't get there, the instructions I found for workarounds didn't seem to work anymore.
So the solution I landed on was to set up an Ubuntu VM, and follow some instructions from https://stackoverflow.com/q/51986932 to patch Ruby to work with the version of OpenSSL we have access to!
And it was enough of a challenge that I figured that, rather than setting up the Vagrantfile elsewhere, it would be helpful documentation to do it here, even if we scrap the Vagrantfile etc later once we're in a new stable environment.