Does this install dependencies on a per-script basis? Can different scripts' dependencies conflict with each other? I think I saw this when I initially put together the list, but I didn't include Ruby because I wasn't sure how it worked.

I'll add Ruby if conflicts are normally impossible. (If conflicts are possible, the method is equivalent to shelling out to the language's package manager at the top of the script before the imports, which you can do in most scripting languages.)