I'm not good at programming, but it seems that the best way to make this probably would be...

A competition, but you can have teams. So people who like to work together can, and people who like to work alone can. This way, you don't have people who don't like to work together having to if they want to help program it, you won't have conflicting programming styles, you will be able to pick your favorite, and everyone gets to choose how they want to make it.