WebSharper is an F#-based web programming platform. It lets you develop web applications from a single F# codebase, to be run in the .NET environment on the server, the JavaScript environment on the browser, or both. WebSharper enjoys type safety of F# and code completion of Microsoft Visual Studio, making it a very productive envionment for developing JavaScript. WebSharper server-side components make communicating with the server is as easy as calling a function.

WebSharper includes:

  • A compiler from assemblies to JavaScript.

  • Extensible support for a large part of the F# and .NET standard library (including sequences, events and asynchronous workflows) on the client.

  • Support for type-safe programming with the standard JavaScript library and DOM.

  • F# bindings to a number of third-party libraries including jQuery.

  • Formlets - an innovative library for type-safe web formcombinators.

  • Support for seamless client/server communication.

  • Tools for embedding raw JavaScript code and binding to external JavaScript codebases from F#.

  • Integration with ASP.NET andMicrosoft Visual Studio.

  • Resource dependency management for CSS, image and other supporting files.


Since January 2012, WebSharper source code is available under GNU Affero GPL, see LICENSE.txt in the source. Alternative licensing schemes are available for users who find AGPL terms too restrictive, see the website for details.


The easiest way to obtain WebSharper is by using the binary installer (see websharper.com or the Downloads section of this project). The installer adds templates to Visual Studio and makes it easy to get started.

Alternatively, you can try getting the cutting-edge alpha release - we are currently in the process of testing it and preparing matching extensions before making it official. The binaries are available on NuGet under the 2.5.*-alpha version. There is also a sample AppHarbor application you can clone to quickly get started: websharper-bootstrap-site.

To obtain the source code, please use our Bitbucket repository. If you prefer git, a GitHub clone of the repository is also available.


Build requirements:

  • Microsoft .NET Framework 4.0

  • F#

To compile, run MSBuild.exe in the root directory of the checkout. This will download and reference required Mono.Cecil libraries and Microsoft Ajax Minifier tasks automatically.

For example, using PowerShell:

set-alias msb C:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe
msb /P:Platform=AnyCPU /Configuration:Release

Solutions provided for Microsoft Visual Studio 2010 and 2011 under the build directory in the source, but these products are not required to build WebSharper.


Please refer to the WebSharper website for tutorials and samples. The website also distributes a manual in PDF format. There are plans to make the manual, tutorial and sample sources available as part of this repository in the future.


The WebSharper website provides several extensions that make third-party JavaScript frameworks available for easy use in WebSharper projects (see the Download section). The source code of the extensions will be made available as well, as time permits.


The preferred way to report bug and request enhancements is through the built-in issue service.


WebSharper is being developed by IntelliFactory. Please feel free to contact us.

For public discussions we also recommend using FPish, the functional programming community site built with WebSharper.