capistrano_and_bundler.rb

namespace :bundler do
  task :create_symlink, :roles => :app do
    bundle_dir = "#{release_path}/vendor/bundle"
    shared_dir = "#{shared_path}/bundle"
    
    run "rm -rf #{bundle_dir}"
    run "mkdir -p #{shared_dir} && ln -s #{shared_dir} #{bundle_dir}"
  end

  task :bundle_new_release, :roles => :app do
    bundler.create_symlink
    run "cd #{release_path} && bundle install --production --without development test"
  end
end

after 'deploy:update_code', 'bundler:bundle_new_release'