[$] Microblogging with ActivityPub

As of late, concerns about the future of Twitter have caused many of its
users to seek alternatives. Amid this upheaval, an open-source
microblogging service called Mastodon has received a great deal of
attention. Mastodon is not reliant on any single company or central
authority to run its servers; anyone can run their own. Servers communicate
with each other, allowing people on different servers to send each other
messages and follow each other's posts. Mastodon doesn't just talk to
itself, though; it can exchange messages with anything that speaks the ActivityPub protocol.
There are many such implementations, so someone who wants to deploy their own
microblogging service enjoys a variety of choices.