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Phusion Passenger 4.0.45: major Node.js and Meteor compatibility improvements

By Hongli Lai on June 12th, 2014

Phusion Passenger is a fast and robust web server and application server for Ruby, Python, Node.js and Meteor. Passenger takes a lot of complexity out of deploying web apps, and adds powerful enterprise-grade features that are useful in production. High-profile companies such as Apple, New York Times, AirBnB, Juniper, American Express, etc are already using it, as well as over 350.000 websites.

Phusion Passenger is under constant maintenance and development. Version 4.0.45 is a bugfix release.

Phusion Passenger also has an Enterprise version which comes with a wide array of additional features. By buying Phusion Passenger Enterprise you will directly sponsor the development of the open source version.

Recent changes

  • Major improvements in Node.js and Meteor compatibility. Older Phusion Passenger versions implemented Node.js support by emulating Node.js’ HTTP library. This approach was found to be unsustainable, so we’ve abandoned that approach and replaced it with a much simpler approach that does not involve emulating the HTTP library.
  • Introduced support for sticky sessions. Sticky sessions are useful — or even required — for apps that store state inside process memory. Prominent examples include SockJS,, faye-websocket and Meteor. Sticky sessions are required to make the aforementioned examples work in multi-process scenarios. By introducing sticky sessions support, we’ve much improved WebSocket support and support for the aforementioned libraries and frameworks.
  • Due to user demand, GET requests with request bodies are once again supported. Support for these kinds of requests was removed in 4.0.42 in an attempt to increase the strictness and robustness of our request handling code. It has been determined that GET requests with request bodies can be adequately supported without degrading robustness in Phusion Passenger. However, GET requests with both request bodies and WebSocket upgrade headers are unsupported. Fixes issue #1092.
  • [Enterprise] The Flying Passenger feature is now also available on Apache.
  • Fixed some issues with RVM mixed mode support, issue #1121.
  • Fixed Passenger Standalone complaining about not finding PassengerHelperAgent during startup.
  • Fixed various minor issues such as #1190 and #1197.
  • The download timeout for passenger-install-nginx-module has been increased. Patch by 亀田 義裕.

Installing or upgrading to 4.0.45

OS X OS X Debian Debian Ubuntu Ubuntu
Heroku Heroku Ruby gem Ruby gem Tarball Tarball


Phusion Passenger’s core is open source. Please fork or watch us on Github. 🙂

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