Solarbird 
kinda shitty test version two but it is a test version two
oh yeah it tested fine on a little 12-mile errands ride so we’ll keep testing it
i have several ideas for how I want to make a real/final version
here are the object holders it is replacing
it’s nice not to ever be touching that bike lock holster when I pedal anymore
I definitely want the final to zip shut. velcro is scary. xD
going back on forth on top or bottom zipper for comfort reasons
Jon A. Cruz@moira trying to think of some of the better closures I've used. Zippers make me a little nervous for non-trivial loads. Some sort of clasp or latch mechanism might be good. Trying to remember details from my army days.
@joncruz zippers have always been fine for me on bikes, you just have to buy the good ones
(and there are not good ones) (lots of not good ones) (mostly you can buy YKK and not worry that much more about it) (there's another brand too but I forget atm what it is)
@moira did a quick image search last night, and found that some of what I was thinking was reflected in motorcycle saddlebags, among other things. Some depends on how your bag opens, but one common approach is to use plastic snap buckles, with or without straps and other buckles. A couple of U shapes brackets across the top tube with clips out at right angles near its bottom would do the trick while avoiding your legs. Also matches some of the better bike bags I've had in the past. Subjective.