backtrace output

/Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/variables.rb:82:in `block in fetch': `rvm_ruby_string_evaluated' not found (IndexError)
  from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/variables.rb:110:in `block in protect'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/variables.rb:110:in `synchronize'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/variables.rb:110:in `protect'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/variables.rb:78:in `fetch'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/namespaces.rb:191:in `method_missing'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/rvm-capistrano-1.4.0.rc2/lib/rvm/capistrano/install_ruby.rb:35:in `block (3 levels) in <top (required)>'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/execution.rb:138:in `instance_eval'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/execution.rb:138:in `invoke_task_directly'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/callbacks.rb:25:in `invoke_task_directly_with_callbacks'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/execution.rb:89:in `execute_task'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/configuration/execution.rb:101:in `find_and_execute_task'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/execute.rb:46:in `block in execute_requested_actions'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/execute.rb:45:in `each'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/execute.rb:45:in `execute_requested_actions'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/help.rb:19:in `execute_requested_actions_with_help'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/execute.rb:34:in `execute!'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/lib/capistrano/cli/execute.rb:14:in `execute'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/gems/capistrano-2.15.4/bin/cap:4:in `<top (required)>'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/bin/cap:23:in `load'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/bin/cap:23:in `<main>'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/bin/ruby_noexec_wrapper:14:in `eval'
	from /Users/austin/.rvm/gems/ruby-2.0.0-p195@myapp/bin/ruby_noexec_wrapper:14:in `<main>'

deploy.rb

require 'capistrano/ext/multistage'

set :application, "myapp"
set :scm, :git
set :repository, "[email protected]:owner/myapp.git"
set :use_sudo, true
set :rvm_type, :user
set :rvm_ruby_string, "2.0.0-p195@myapp"
set :rvm_install_ruby, :install

# multistage
set :stages, %w(staging production)
set :default_stage, "staging"

set :deploy_to, "/var/www/#{application}"
set :shared_path, "/var/www/shared/#{application}"

staging.rb

set :rails_env, "staging"
set :unicorn_env, "staging"
set :app_env, "staging"

server "staging", :app, :web, :db, :jobs, :primary => true

require "rvm/capistrano"