I used mod perl for a long time. However the trend (because IMO its far superior and more flexible and better performance) is to run HTTP servers within your code, rather than have HTTP servers call your code.

For example you can use AnyEvent::HTTPD to easily turn basically any perl script into its own webserver, to do whatever when you get requests. Nginx can then act as a proxy to it which seems to be the most popular way webservers are done now.