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The Social Web Working Group invites implementation of a revised Candidate Recommendation of ActivityPub. ActivityPub allows websites a direct social connection to user software, including Follow, Like, Share, and Comment, without an intermediate social network provider. It is built on the ActivityStreams 2.0 data format, and iterates on the design of OStatus, which last month saw a wave of mainstream interest with Mastodon. It provides a client to server API for creating, updating and deleting content, as well as a federated server to server API for delivering notifications and subscribing to content.