The new ASP.NET 5 framework coming from Microsoft has some significant architectural changes that make it more modular, cross-platform and leaner than previous versions. The following are some of the key new features for developing light weight web based applications using the new ASP.NET 5 framework.
Use the Full .NET CLR, Core CLR or Cross Platform CLR
One of the key changes in ASP.NET 5 is the ability to choose from full .NET CLR, a more streamlined Core CLR or a cross-platform CLR. The Core CLR is only 11 megabytes compared to the full .NET CLR at 200 megabytes. Instead of requiring the entire framework, you can add the specific libraries you need through NuGet packages.
The cross-platform CLR will target Windows, OS X and Linux.
Embed the CLR with Your Application
In the current and older versions of the .NET framework, you deployed the CLR as a global installation. If you upgraded the framework, it could impact every application running on the server.
In the new ASP.NET 5 architecture, you can run different versions side by side and you can embed the Core CLR and any dependent packages with your application.
No More Web.Config!
One of the key advantages of ASP.NET 5 is a replacement for the reliable but inflexible Web.Config. You can now store configuration information in variety of formats including JSON and XML.
One of the key dependencies for any ASP.NET application is IIS. While IIS will still be the default method to host an ASP.NET application, you can now target other hosting environments. For example, the ASP.NET 5 framework provides its own console app called WebListener that can host ASP.NET applications without the need for IIS.
For more information on ASP.NET 5 see the ASP.NET vNext web site.