backbone.js + underscore.js + ??? = good localization

Starting a localization process for one of projects. Currently looking for localization of backbone and underscore parts. i18n plugin from require.js seems to do almost all that I need, but... there is a strange feeling that everything is too simple... Looking around on the web found some frameworks, projects but they don't offer anything that I can not get with a plain and simple require.js i18n... Strange... Someone passed through same feeling before? What was the result? :)