Fermenting pickles - sun or shade?
In general, cooler temps mean slower fermentation, and, in my opinion, better flavor.  I would go for a cool, dark place.  Beyond that you'll want to make sure that you have the correct percentage of salt to pickle...3.5% by weight at least.  Too low a concentration, and bad bacteria will survive.  There are lots of internet resources, but Sandor Katz is the expert This is his site.