Composite C1 CMS is a fully featured free open source web content management system developed for (and by) web professionals who focus on customized websites.
The user interface is very functional and task oriented and enables users of varying skills to complete tasks and cooperate using familiar tools and guides. High-end technical skills are not a requirement to build websites with Composite C1, but if you've got them, you will own the system.
Developers can manage layouts and extend the system using any choice of ASP.NET Razor, Web Forms, MVC and XSLT. Like the back-end developers, front-end developers are highly empowered and able to control website look and feel down to minute detail.
With the system being based on .NET 4.5 developers have access to the latest technologies, a pluggable well designed architecture & API and full LINQ data access. This is a flexible system with easy setup, easy Windows Azure migration, both file based and SQL Server data support, a lot of free easy-to-install add-ons and a set of premium offerings (corporate website add-ons, support, upgrade services, full warranty licensing). All of this makes Composite C1 a customizable and scalable product, both in terms of price, service and complexity.
A very strong emphasis on quality, documentation, flexibility and developer community. So far all major releases of Composite C1 have been voted “best CMS” at CodePlex.