This is a personal initiative (not backed by the Core Team) that aims to make CiviCRM work without a CMS. This was possible some time ago, but not very popular and was removed somewhere in the 3.x series.
As CiviCRM has evolved, and so has content management systems, and how organisations manage their CRM, it seems like a good time to bring CiviCRM Standalone back.
* A lot of organizations do not expose their CRM, or they might only expose specific forms, on a sub-domain.
* Managing a website and a CRM coupled together can be challenging.
* CMSes have become more and more complex, with increasing conflicts between CiviCRM and the CRM.
