If you are on windows 10, you can simply use a linux subsystem. That ain’t what we’re talmbout here.
babun is a cygwin based shell with a bunch of defaults added that aren’t included with the portablegit install that comes with github for windows. Some of those defaults that I wanted to include, indeed what pushed me to try babun, are zsh and oh-my-zsh. (I was tryna figure out a way to include it in the portablegit, but ran into some roadblocks, such as no autoconf)
Setting up a custom shell in g4w is pretty straightforward, just open up options… and add the following to the Custom selection for Default Shell: