The Mono Project is an open source version of the Microsoft.NET development platform. Incorporating key .NET compliant components, including a C# compiler, a Common Language Runtime just-in-time compiler, and a full suite of class libraries, the Mono Project will enable developers to create .NET applications and run them on Windows or any Mono-supported platform. Besides greatly improving the efficiency of development in the open source world, the Mono Project will allow the creation of operating-system-independent programs. Although primarily developed on Linux, Mono is being ported to as many operating systems as possible.

Microsoft.NET development tools, which include the C# compiler and Common Language Infrastructure (CLI), let programs written in C# and other languages run on non-Windows operating systems. The Mono Project development platform provides open source developers with a true "build once, deploy anywhere" tool-set taking advantage of the myriad of services enabled by Microsoft.NET.

The Mono Project will provide three key elements in a development framework designed to allow developers to quickly create, deploy and run .NET compatible applications on non-Windows platform. A C# compiler extending the GNOME development platform will allow Linux developers to create .NET compatible applications. These developers will also be able to build upon a complete implementation of class libraries compatible with the Microsoft CLI, enabling developers to create end-user applications as well as powerful web services using the database functionality available on open source systems. Portation of Mono yields versions of the Microsoft Common Language Run-Time (CLR) just-in-time (JIT) run-time engine will allow non-Windows systems to run .NET applications built on Windows, Linux or UNIX platforms.

The example in the previous section can be run using the CLR hosting ability of Virtuoso, but only with the precompiled assembly which has to be deployed into the Mono/lib directory of the Mono installation.

The Virtuoso installer on non-Windows platforms for which there is a port of Mono available installs the latest Mono CLR. This is required for the Virtuoso server to host .Net applications on non-Windows platforms.

Only a compiler for C#. Inline ASPX code using C# is a safe way to write and experience ASPX hosted from Virtuoso. Although this goes completely against the programming practice guidelines for .Net

The only permissible Application Domain is the Mono application. ASP.Net applications should have their own self containable Application Domain - the ./bin directory. Mono does not support this as of yet. The work around is to place all assemblies into the Mono domain.