NEW!
CSHTML5 has now become OpenSilver!

We are happy to announce that CSHTML5 has been significantly improved and rebranded to 'OpenSilver', which stands for 'Open-source reimplementation of Silverlight'. It is fully backward compatible and it can be downloaded from OpenSilver.net. Upgrading from CSHTML5 to OpenSilver is very easy.
Read the FAQ

Extensions for CSHTML5

 

Proprietary extensions:

    - Kendo UI wrappers for CSHTML5

 

Open-Source extensions:

    - Chart controls (Plotly)

    - WebSockets

    - JSON Serialization / Deserialization

    - JSONP Calls

    - SignalR

    - WebGL 3D / Three.js by rkmore

    - Particles & Weather by TaterJuice

    - Busy Indicator Spinner by Sesztak

    - FileOpenDialog

    - FileSaver

    - ZipFile

   - DatePicker by TaterJuice

    - TimePicker by TaterJuice

    - jQuery.ajax

    - PrintHelper

    - Unofficial ArcGIS Mapping control (in progress)

    - Compose Email

    - SHA1 Hash Function

 

More extensions, updates, and discussions can be found on the Extensions and Plugins section of the Forums.

You may also be interested to read: How to Create Extensions for CSHTML5.