# \[Rails3\] Rails 3 app in one file

**URL:** <https://www.ruby-forum.com/t/rails3-rails-3-app-in-one-file/185851>\
**Category:** Rails\
**Created:** [March 27, 2010, 10:51am UTC](https://www.ruby-forum.com/t/rails3-rails-3-app-in-one-file/185851 "2010-03-27T10:51:13Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Drogomir](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/5fc32e/32.png) [@Drogomir](https://www.ruby-forum.com/u/Drogomir)\
**Post date:** [March 27, 2010, 10:51am UTC](https://www.ruby-forum.com/t/rails3-rails-3-app-in-one-file/185851/1 "2010-03-27T10:51:13Z")

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Hi,

I’ve tried to run [config.ru](http://config.ru) file provided by Yehuda K.:  
[omg.rb · GitHub](http://gist.github.com/330207)

After running it and pointing browser to localhost:3000/foo I get  
“RoutingError: uninitialized contant FooController” error.

Have anyone else tried it? Is there anything more to add?

My Gemfile is one liner:  
gem ‘rails’, :git =\> “git://github.com/rails/rails.git”