Getting Started On Windows


Install any edition of Visual Studio version 2019 or newer.

Note: The MOSA source code repository includes the Qemu virtual emulator for Windows.


The MOSA project is available as a zip download or via git:

git clone

If download via zip, unzip the file.


Execute the Compiler.bat script in the base directory in the root directory to build and compile all the MOSA tools, kernels and demos.


A successful build will display a Build succedded message (like below). Warnings may be ignored.

[... lines removed...]

Build succeeded.

[... lines removed...]

1 Warning(s)
0 Error(s)

Time Elapsed 00:00:01.48


To launch one of the demo application, execute the Launcher.bat script to start the MOSA Launcher Tool. This tool:

  • Compiles the operating system

  • Creates a virtual disk image, with the compiled binary and boot loader

  • Launches a virtual machine instance (using QEMU by default)

By default, the CoolWorld demo operating system is pre-selected. Click the Compile and Run button to compile and launch the demo.

Starter Project

A pre-built starter C# project template is available for experimentation.

Option #1 (Preferred - includes the entire MOSA project):

Open the Source\Mosa.sln solution with Visual Studio and locate the Mosa.Demo.MyWorld.x86 under Demos.

Next, set the project as Set as Startup Project.

Option #2 (Only the starter project):

Open the Source\Mosa.Demo.MyWorld.x86\Mosa.Demo.MyWorld.x86.csproj project with Visual Studio.

To compile and launch the application within a virtual machine, simply click on the Start button.