This document outlines 12 components for building sustainable open source communities: 1) having shared purpose and values, 2) open communication, 3) low entry barriers, 4) contribution pathways, 5) consistency while allowing for progress, 6) mentorship, 7) rewards and recognition, 8) tools and resources, 9) a code of conduct, 10) storytelling, 11) diversity, equity and inclusion, and 12) celebration. The document argues that these components help attract and engage community members by giving them a sense of belonging, ownership, and meaningful ways to contribute to the shared goals of the community.