Is it feasible to use Mustache templates (http://mustache.github.com) in a theme instead of the default Razor syntax?
As most frontend dev’s we work with are on a Mac having to use Razor is creating a bottleneck in development, and I would prefer use a templating engine that can be rendered cross platform.
You can in principle use any view engine that is compatible with ASP.NET MVC, but you really shouldn’t. You are going to fight with the system every step of the way. All of the themes and modules that you’ll find (and you’ll need them), as well as all the views in the core, are going to be using Razor. It’s just a very, very bad idea.
You should try to find a CMS that uses Mustache natively as its default templating language, or learn Razor.