is there an open source social single-sign-on facade?

I recently found the jainrain engage product that helps streamline the process of connecting a drupal application to single-sign-on of all major social network.

I appreciate it because it reduces to 1 API all the different APIs you may encounter on the different开发者_JAVA技巧 networks.

Is there an open source version of such a 1-size-fits-all API ?

Thanks for your help

Maybe this one? http://hybridauth.sourceforge.net/

I've been using the OpenID Selector module lately, with good results. It doesn't offer all the functionality that Janrain's solution does, but it's a good start.