Despite my optimism regarding getting my Rails app running under Apache httpd with Passenger, I wasn’t counting on Arch Linux getting in the way.
After non-sensical permission denied errors in the Apache logs, with Passenger running, but nothing in the Rails app logs, I figured that the problem was that Passenger was actually starting the app.
Running Passenger standalone seemed to suggest it wanted to install and run nginx trying to serve content from an Apache httpd confguration directory (which doesn’t exist). The lack of any errors with regard to Rails not actually starting doesn’t help.
It could be that the Ruby/gems/Rails install is pretty messed up (hard to imagine, I know) but it looks like I’m back to laptop Fedora Apache after another day lost faffing around with the web server side rather than working on code; I’m not working on a Rails app that has sensitive config values in code files that can be checked into GitHub and Apache httpd is the only way to go.