The alternative already exists, why isn't it being used?
Can you tell which alternatives? They are either similar or inferior to Upwork, or are still new and relatively unknown (and therefore there are not much jobs in their platform). It's a huge dilemma.
http://bitkick.org/
My partner and I just kicked this off. We've got 6mo of runway and must acquire 100k freelancers in that time. Its chicken & egg, of course, we've decided to start on the talent side.We are also looking for freelancers to participate in market research interviews to help guide our build out.