Windows:
You must be running 64 bit Windows 10, version 1703 or newer.
Rustup:
As mentioned in development.md, rustup must be installed. If you're on ARM Windows, you must set the default target to x86_64-pc-windows-msvc.
Visual Studio:
Install Visual Studio Community Edition from Microsoft. Once you've downloaded the installer, open it, and select "Desktop Development with C++" on the left, leaving the options shown on the right as is.
MSYS:
Install msys2 into the default folder location.
After installation completes, run msys2, and run the following command:
$ pacman -S git rsync
Edit your PATH environmental variable and add c:\msys64\usr\bin to it, and reboot.
If you have native Windows apps relying on Git, e.g. the PowerShell extension posh-git, you may want to install Git for Windows and put it on the path instead, as msys Git may cause issues with them. You'll need to make sure rsync is available some other way.
Source folder:
Anki's source files do not need to be in a specific location, but it's best to avoid long paths, as they can cause problems. Spaces in the path may cause problems.
To play and record audio during development, mpv.exe and lame.exe must be on the path.
For info on running tests, building wheels and so on, please see Development.