If you want a true BDD framework then maybe consider Yadda. It integrates with mocha, jasmine, nodeunit, qunit, zombie and casperjs, to support feature files, e.g.
Scenario: provides the version of all services
given service x is running
and service y is running
when I request the service versions
then service x should be version 0.0.1
and service y should be version 0.0.2
