This is a minimal Rails application that demonstrates cross-site login with Tender. I created it to test some single-sign on features in Tender, but thought a demo might be useful to others. It took a couple plugins, one gem dependency, a generator and a few lines of code. Total dev time was maybe 30 minutes. To use: $ bundle install $ open app/models/user.rb # change TENDER_SITE and TENDER_SSO_KEY. $ rails server Have fun.