Things to check out:

• audit tool's $HOME/.lighttpd.conf files
  • how many?
  • what sorts of things to they do?
• Try running nginx on the job grid
• Build and test a PHP 7.3 + nginx + ??? container for the kubernetes cluster

end user docs/tutorials are difficult to find

Examples, please? The official lighttpd documentation is on https://wiki.lighttpd.net/
lighttpd forums for questions are at https://redmine.lighttpd.net/projects/lighttpd/boards

there are bugs features in it that block some user customizations

Examples, please? I do not frequent phabricator here, but a long time ago, the hurdle was (and probably continues to be) that wikimedia runs older versions of lighttpd and might benefit from running newer versions of lighttpd.

> it is currently without a Debian maintainer

The Debian bug you references was updated in Feb 2020 to indicate that it is and was maintained, but that the Debian bug had mistakenly not been closed.

Build service probably makes this investigation and implementation obsolete in that we are actively directing folks away from the shared containers and towards building their own.