[antoncohen]

I think a caching daemon would be good option for PHP, but it does add a level of complexity.

Another option would be to add EnvKey support to confd (or similar project), and provide config and template files that write the env vars to Apache and Nginx configs, and reload when they change.

Though neither confd or a daemon would work for PHP sites that use a PaaS or shared hosting, which I think is a large percentage of the market for PHP.

Using one of the existing PHP caching solutions (like opcache) might be an option.