ruby.social is one of the many independent Mastodon servers you can use to participate in the fediverse.
If you are interested in the Ruby programming language, come join us! Tell us about yourself when signing up.
If you just want to join Mastodon, another server will be a better place for you.
If you prefer using a "paper" agenda, you might like my hyperlinked PDF page-a-day calendar generator optimized for the reMarkable tablet: https://github.com/osresearch/pdfcal