Asana employee here. We have 58 people, about 20 of which are engineers. Even just focusing on engineers, there's so much we'd like to do and growing the team enables us to work on more of those things. It took 3 engineers to build the recently launched calendar feature, for example. And then there are other product features, growth, mobile, platform, data, and a bunch of us working on infrastructure (from keeping the site running to making it fast).