Yeah, more than 4600 employees seems wild for Pinterest. Reddit seems to have about 2,2k which still seems a lot but is less than half. I wonder how many of those are programmers and how many are infra, marketing, management, legal etc.

The 15% included contractors. Many of the Mobile developers were South American contractors.

I would imagine the minority are technical. You usually need a large sales team to handle the relationships in ad sales.