The best "architects" serve as facilitators, rather than deciding themselves how software is built. They have to be reading the code, but they don't themselves have to be coding to be effective.
You don't need one until you've got 30-70 engineers, but a strong group of collaborative architects is the most important thing for keeping software development effective and efficient at the 30-1,000 engineer range.
You don't need one until you've got 30-70 engineers, but a strong group of collaborative architects is the most important thing for keeping software development effective and efficient at the 30-1,000 engineer range.