Stuff like the current version of OpenProject relies on Ruby 3.4 so Passenger supporting Ruby 3.4 is also a requirement (at least when running it in a setup like this). Using OpenProject 15.4.0 I was able to test Ruby 3.4 support by expanding the list of supported Ruby versions via adding ruby34 to USE_RUBY of the following packages: * www-apache/passenger 6.0.26 * dev-ruby/rackup 2.2.1 * dev-ruby/rack 3.0.14 I didn't do much testing but Passenger as well as the application (OpenProject 15.4.0) seem to run fine. Reproducible: Always Steps to Reproduce: 1. Try to install www-apache/passenger with RUBY_TARGETS="ruby34" Actual Results: Unable to install Passenger with Ruby 3.4 support / for RUBY_TARGETS="ruby34". Expected Results: Being able to install Passenger with Ruby 3.4 support / for RUBY_TARGETS="ruby34".