Yuri, you may be interested in some
design notes I wrote a few months ago, about document schemas for social apps. (I’ve done some work on a social app as a personal project, though nothing I plan to commercialize.)
Also, when you post a job listing you should include details other than just your subject line. For instance, the platform(s) you’ll be developing for, if you’re looking for people in any geographic area, hourly rates, etc. I don’t see any problem with posting such offers here, at least not until the volume of them gets too high to manage (and even that would be a good problem to have!)
—Jens