Frank RingMastodon is being developed by a non-profit organization.
Do you mean that Nostr is literally built by the community?
GNU social JP is a social network, courtesy of GNU social JP管理人. It runs on GNU social, version 2.0.2-dev, available under the GNU Affero General Public License.
All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.