Hiring a contractor is a good idea, but make sure they are hired with the potential to become a technical cofounder.
My suggestion would be to hire someone who can rewrite the PHP code into something more maintainable like Javascript, Ruby, or Python. And make sure they have a plan for scalable infrastructure (either via a PaaS like Heroku/App Engine or if they have the chops, a real DevOps infrastructure).
My suggestion would be to hire someone who can rewrite the PHP code into something more maintainable like Javascript, Ruby, or Python. And make sure they have a plan for scalable infrastructure (either via a PaaS like Heroku/App Engine or if they have the chops, a real DevOps infrastructure).