Can you share what worked for you in building a community?

One of the most counterintuitive quote I hear is: "do things that don't scale" :-D, it's so right: you can't have friends at scale, friendship is a slow very intimate process. But at the same time, you need hundreds of people in the community, and no one has hundreds of friends (expect politicians, and I wouldn't be like them :-p). Yeah, so who has some advice to share