Ruby

Actions has three embedded MSYS2 installs, as they currently install the three Windows Rubies with 'DevKits'. So, MinGW could be built/tested on Actions.

I have a GH action at https://github.com/MSP-Greg/msys2-action that's used in Puma's CI, it allows updating the 'toolchain' and additional packages (typically things like ragel, openssl, etc).

JFYI...