Error: Rack app won't run -- bundler/setup

I'm completely new to Ruby (and RoR) and I'm trying to set up a local environment to help work on a site. Ideally, I would work on it locally, and then commit the changes to github and push it further down the pipeline from there.

I'm on a brand new Macbook Pro running OSX Lion.

I have had much trouble trying to get it work:

Installed Xcode Command Line Tools and RVM couldn't install latest version of ruby because it failed to compile with LLVM (Lion default compiler)
compiled ruby using a special flag it asked me to use (forgot what it was), but then was having trouble with Postgres and Pow
Tried installing a standalone GCC to compile ruby correctly thinking it may solve the problem. Pow still gave me errors.

I have tried removing and installing everything I could think of, and still nothing. I stress: I'm a noob.

I finally found a script called railsready that sets up ruby and RoR for you (https://github.com/joshfng/railsready) which failed to recognize Xcode since Lion installs it into Applications (the script checked for it by looking for an Xcode .plist file in Library/Developer). The author helped be out by updating the code to look for gcc instead and it tried installing but failed because it couldn't write to my .bash_profile. I removed it and tried it again, and it worked.

I installed Pow so I can have it run on a custom domain (website.dev) and have multiple apps under different domains. Now it's giving me this error and I have no idea what it means or how to go about it.

I would really appreciate any help. Most ruby guys I talk to have no idea what this is about, and why Lion is so much trouble to set up on. They are on older (Snow Leopard) machines.

The Error

Your Rack app raised an exception when Pow tried to run it.
LoadError: no such file to load -- bundler/setup
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in `require'
~/Github/letsordernow/config/boot.rb:6
~/Github/letsordernow/config/application.rb:1:in `require'
~/Github/letsordernow/config/application.rb:1
~/Github/letsordernow/config/environment.rb:2:in `require'
~/Github/letsordernow/config/environment.rb:2
~/Github/letsordernow/config.ru:3:in `require'
~/Github/letsordernow/config.ru:3
~/Library/Application Support/Pow/Versions/0.3.2/node_modules/nack/lib/nack/builder.rb:4:in `instance_eval'
~/Library/Application    Support/Pow/Versions/0.3.2/node_modules/nack/lib/nack/builder.rb:4:in `initialize'
~/Github/letsordernow/config.ru:1:in `new'
~/Github/letsordernow/config.ru:1

Solution

Welcome to Ruby On Rails. :)

You're going to love the new Rails.app Kickstarter project by Yehuda Katz:

http://www.kickstarter.com/projects/1397300529/railsapp

My advice for now:

Standalone GCC is good. You're doing this right.
To use RVM with Lion and non-LLVM, read about compiling Ruby with clang: Can't install Ruby under Lion with RVM – GCC issues
In each of your Rails projects, run this which may clean up your Pow issues:
```
bundle install
```
Make sure each of your projects has a .rvmrc file pointing to the correct ruby version and gemset.
My two cents is to try to get up and running without RVM and Pow to start. These aren't needed and they have quirks with paths and glitches (IMHO). I personally prefer to use bundler to manage gemsets, and the rbenv tool and ruby-build tool for managing Ruby versions. See https://github.com/sstephenson/rbenv
Pow is nifty but tricky. It has a history of quirky setup (IMHO). My two cents is to get up and running with webrick first (i.e. make sure you can do "rails s" to start a local server) and then I personally like Apache and Passenger (or Thin). For Pow help on quirky setup see https://github.com/37signals/pow/issues/119