This document provides an overview of open source tools and libraries that can be used for .NET projects. It lists many popular options for IDEs, source control, package management, continuous integration servers, metrics, build scripts, ORM, IoC containers, database management, APIs, unit testing, mocking, acceptance testing, application automation, HTTP libraries, JSON, JavaScript libraries, routing, JavaScript MVC frameworks, view engines, roles and access, CoffeeScript, SASS/LESS, CSS libraries, and Visual Studio extensions.