Open Source

Microsoft continues its commitment to open source. We not only host projects at the CodePlex forge and support many open source projects, but we also create our own open-source projects that the community can improve and extend. In addition to Microsoft-supported open source projects, there are thousands of great open source projects, applications, and libraries that you can use with ASP.NET today. Here you'll find a few of our favorites. If you're looking for Samples, there's lots of samples here as well as on http://code.msdn.microsoft.com. We'll update these pages as we come upon other cool projects. - Jon Galloway and Scott Hanselman

Better CMS

Better CMS is a publishing focused and developer friendly .NET Open Source CMS.

FubuMVC

A compositional, convention-based framework for complex web applications.

Service Stack

Thoughtfully architected, obscenely fast, thoroughly enjoyable web services for all.

NHibernate

NHibernate is a mature, open source object-relational mapper for the .NET framework. It's actively developed, fully featured and used in thousands of successful projects.

NancyFx

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

Simple.Web

A lightweight, object-oriented (Model-View-Handler) framework for modern web development in .NET.

Oak

Frictionless development for ASP.NET MVC single page web apps. Prototypical and dynamic capabilities brought to C#.

OpenRasta

OpenRasta is an open-source .NET framework for building everything web, from web sites to RESTful APIs

ASP.NET MVC, Web API, and ASP.NET Web Pages (aka Razor)

The source code for ASP.NET MVC, ASP.NET Web API and ASP.NET Web Pages (aka Razor) are available under an open source license. Developers outside of Microsoft may submit patches and code contributions that the Microsoft development team will review for potential inclusion. These frameworks continue to be fully supported and staffed by Microsoft.

Orchard CMS

Orchard is an Open Source Content Management System built on ASP.NET MVC, nHibernate and Autofac.

.less

Write regular CSS with your .NET apps, then add a few variables, mixins and nested rules. “.less” (pronounced dot-less) is a .NET port of the funky ruby LESS library.

Glimpse

At its core Glimpse allows you to debug your web site or web service right in the browser. Glimpse allows you to "Glimpse" into what's going on in your web server. In other words what Firebug is to debugging your client side code, Glimpse is to debugging your server within the client.

DotNetOpenAuth

DotNetOpenAuth is a well-established open source library that bring OpenID, OAuth, and ICard capabilities to the Microsoft .NET Framework.

jQuery

jQuery is a fast and concise JavaScript Library that simplifies HTML document traversing, event handling, animating, and Ajax interactions for rapid web development. jQuery is designed to change the way that you write JavaScript.

ELMAH

ELMAH (Error Logging Modules and Handlers) is an application-wide error logging facility that is completely pluggable. It can be dynamically added to a running ASP.NET web application, or even all ASP.NET web applications on a machine, without any need for re-compilation or re-deployment.

Mini Profiler

A simple but effective mini-profiler for ASP.NET MVC and ASP.NET. It does not attach itself to every single method call. Instead, it provides: an ADO.NET profiler and a pragmatic Step instrumentation that you can add to code you want to explicitly profile.

Massive

Massive is a "wrapper" for your DB tables and uses System.Dynamic extensively. Drop the code file into your app and change it as you wish. It’s a micro-ORM that hides some things and embraces others.

Dapper

Dapper is a single file you can drop in to your project that will extend your IDbConnection interface. It’s a “micro-ORM” for people who love SQL.

n2cms

N2 is a lightweight CMS framework. With just a few strokes of your keyboard a strongly typed model emerges complete with a management UI.

Chirpy

Chirpy mashes, minifies, and validates your javascript, stylesheet, and dotless files, and can also auto-update T4MVC and other T4 templates.

Combres

Combres is a .NET library which enables minification, compression, combination, and caching of JavaScript and CSS resources for ASP.NET and ASP.NET MVC web applications. Simply put, it helps your applications rank better with YSlow and PageSpeed.

MvcMailer

MvcMailer is an ASP.NET MVC Mailer, inspired by Ruby on Rails ActionMailer, that helps composing Email body using regular ASP.NET MVC views.

MvcContrib

Designed to add functionality and ease-of-use to the ASP.NET MVC Framework, MVC Contrib is useful for developers looking to develop and test UI elements on top of the ASP.NET MVC framework.

MVC HTML5 Templates

Adds EditorTemplates for the new HTML5 input types (including email, tel, and url) to ASP.NET MVC 3 projects.

T4MVC

A T4 template for ASP.NET MVC

NuGet.org

NuGet.org has an extensive directory of open source libraries which you can easily add to your applications via the NuGet package management system.

Wijmo

Wijmo Open is a kit of widgets built on jQueryUI and released to the community. Wijmo Open is open source and is free to use under either the MIT or GPL licenses.