Who on earth would use Freelancer.com for this task
If I was asked to manage a project like this I would insist on the right to interview all hires, any social media site has a huge attack horizon and will end up containing sensitive data, the idea of just outsourcing any of the internet facing security code or infrastructure design to 'some bloke off the internet' appals me, Whilst I might be open to using Computer Science students there would need to be a properly experienced lead dev in place to provide mentoring, skills transfer and Quality Assurance roles.
One warning about this approach is that it is not cheaper than employing experienced developers unless the engagement is going to be at least 6 months. If this is a quick and dirty implementation I would build a team from existing, proven contacts whop could hit the ground running, the $112 would pay for one hour of one of these dev's time, I can deliver it quick and secure or slower but lower cost and secure but not cheap. Don't forget that the level of fines available in case of a data breach in the UK can reach hundreds of thousands of pounds.
The other worry about anyone who would even consider this approach would be that they would almost certainly use a cloud based service and assume that the infrastructure was also secure by default. I wouldn't consider starting development work until the architectural design had been produced and signed off by a web security specialist I knew and trusted.
Biting the hand that feeds IT
