Phusion Passenger

Phusion Passenger (informally known as mod_rails and mod_rack ) is a module for the Apache HTTP server and nginx for deployment of Ruby web applications that comply with the rack interface, especially for Ruby on Rails applications. The module took over from mod_ruby. It is available as a Gem package and is supported on Unix-like systems, such as Unix and Linux.

Phusion Passenger is by the developers of Ruby on Rails as the preferred method to deploy Ruby on Rails applications, recommended. A 2009 survey on Rails hosting with 1215 respondents revealed that almost exclusively Phusion Passenger and Mongrel be used to Deploy Rails applications on production systems, with Phusion Passenger is used somewhat more frequently.

Combined with Ruby Enterprise Edition, the memory requirement for Rails applications can be reduced by about 30 % while the performance to be improved.

Outside the productive use during the development of ships with Ruby WEBrick is used instead of Phusion Passenger often.