VSTO add-in to automatically scan E-Mails for malware

We're an IT-security software vendor that runs a popular free malware analysis webservice at [login to view URL] (more information on our company at [login to view URL] or [login to view URL]). We have already started developing a VSTO add-in for outlook that can take incoming E-Mail attachments or URLs in the E-Mail body and analyze them using our comprehensive and extensive HTTP based RESTful API: [login to view URL] We are 50% done, but the code probably needs refactoring, the add-in itself needs more advanced features implemented, we need testing, etc. which is why we are looking for a senior developer that has a lot of experience and is willing to push through as part of a small, but highly skilled and motivated IT-security startup team. We have a variety of follow-up projects, so this can be an entry into a long-term relationship.