I think it's wonderful that you offered to do that but it simply isn't realistic. Who is going to support this software in the long term? How are you handling privacy concerns? What guarantees can you offer about server security? Who is paying for and maintaining the servers in the long term? What happens (to be blunt) if you die the day after the software is delivered?
There's so, so much wrong with the way governments provision software projects from outside parties. But there is good reason to have contracts the length of the Bible. Picking up work from individuals on a whim is courting disaster.