The best replacement for mod_perl is mod_php.

The best alternatives to mod_perl are rated as following:
★★★★★  mod_php
★★★★★  mod_cgi
★★★★  fastcgi
★★★  plack
  mod_python

Your alternative for mod_perl is not listed? Suggest!
Speaking about mod_perl, one probably shouldn't forget about apache.

Other search terms related to mod_perl and their ratings are:
★★★★★ apache
You have in mind a companion for mod_perl and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of mod_perl in all years. Click on graph for more.
mod_perl
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