Microsoft has released the source code for MS-DOS 4.0 and it's giving me all the nostalgia feels

Ah, the PC in the spare room. Back when "going on the computer" was an event, not a daily necessity, I cut my teeth on MS-DOS games. I didn't really know how they worked, and I wasn't very good, but there a hardware and gaming enthusiast was born. Now Microsoft has released the source code for MS-DOS 4.0 in partnership with IBM, and apparently, all it takes is the logo to make me go all mushy.

This isn't the first time Microsoft has open-sourced MS-DOS, as its GitHub repository already has versions 1.25 and 2.0...