I thought the same thing - the company the person is CTO of builds the petitions website if you click through the link in their bio and then into their projects page
e: This came out worded as if I was disproving, I'm agreeing with the grandparent comment and showing my working
It seems pretty plausible. His tweets give information about why the site crashed, some discussion about how the back-end works, and the company he claims to work for lists the Petitions website as one of their projects.
The whole site is actually open source. Running on Ruby Rails.