ASP.NET Core is a cross-platform .NET framework for building modern cloud-based web applications on Windows, Mac, or Linux.

Dapper - a simple object mapper for .Net

Unity / XNA game patcher and plugin framework

Lightweight, low-ceremony, framework for building HTTP based services on .Net and Mono

General purpose redis client

Virtual File System for Git: Enable Git at Enterprise Scale

A C# implementation of the WebSocket protocol client and server

Javascript Interpreter for .NET

A 100% native C# implementation of ZeroMQ for .NET

[Archived] A cross platform web server for ASP.NET Core. Project moved to https://github.com/aspnet/AspNetCore

Write C# apps with a text editor, nuget and the power of Roslyn!

C# Websocket Implementation

A simple, zero-config DLNA media server, that you can just fire up and be done with it.

Owin Web Server in pure .Net

Script and create SQL Server objects quickly

A lightweight and scalable asynchronous WebSocket listener

CLR (.NET & Mono) binding for 0MQ

libevent2-based HTTP server for C#

HTTP 2.0 with Katana

Node.js connect middleware for .NET using OWIN

Stereogram generator

A multiplayer extension mod for the game SpiderHeck.