I really do appreciate the complexity. I thought about it after my post, particularly about verification of delivery -- it can't just be "bug closed" on the RT. My best idea so far is to agree up front on a test script and the platform(s) on which it must run. If the script passes, the coder gets paid. Incremental payments can come when X% of tests pass. While writing the test script takes effort, too, that's another way of triaging the most important items to address -- i.e. the ones where someone is motivated enough to write a good, testable spec.
And while I get that this is complex, nevertheless, when US comp-sci students can outsource their homework to RentACoder for under $100 a shot, I've got to imagine that there's some existing infrastructure that could facilitate micro-payments for small, focused pieces of work. (And I'm not saying it's rentacoder.com, per se, I'm just using that as an example of the kind of infrastructure I mean.)
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