Who is actually building RPR's tech?

NAR's Realtors Property Resource appears to have subcontracted out significant work, but refuses to clarify

Want to see the future of Real Estate tech?
Limited seating available for ICSF Hacker Connect, July 17

Every year, the National Association of Realtors pours ever-more millions of its members’ dues into a for-profit subsidiary that has never produced a profit and which 88 percent of its members don’t use regularly.