Mastodon Review

The README defines Mastodon as a free, open-source social network server where users can follow friends and discover new ones, and publish links, pictures, text, and video. Servers are interoperable as a federated network, so users on one server can interact with users on another. Features include being part of the Fediverse (anything that implements ActivityPub, including software other than Mastodon, can interact), real-time chronological timeline updates, media attachments, safety and moderation tools (private posts, locked accounts, phrase filtering, muting, blocking, reports, and a moderation system), and an OAuth2 provider with a REST and Streaming API that supports many third-party apps. Requirements listed are Ruby 3.3 or later, PostgreSQL 14 or later, Redis 7.0 or later, Node.js 22 or later, and FFmpeg 5.1 or later. The repository includes Docker and docker-compose configurations and ones for Heroku and Scalingo, and Helm charts live in a separate repository. The project is licensed AGPLv3, copyrighted by Eugen Rochko and the Mastodon authors from 2016.

The repository ships Docker and docker-compose configurations, and the main documentation includes a standalone installation guide. A production instance needs the requirements above, an object storage or disk plan for media, an email service, and a plan for moderation and backups. Running a public server also brings legal and moderation responsibilities that the README does not detail. We did not set up an instance.

Users get a web interface and numerous mobile and desktop apps through the open API. Timelines are chronological rather than algorithmic, and discovery depends on the server you choose and the people you follow. The federation model means the experience varies by instance.

• Federation over ActivityPub, interoperable with the wider Fediverse
• Real-time chronological timelines
• Images and video attachments
• Moderation, reporting, filtering, muting, and blocking tools
• OAuth2 provider and REST and Streaming APIs
• Docker and Helm deployment options

• No single company controls the network, so accounts and communities are portable across the Fediverse
• Mature, large, and still very active, about 50,400 stars and commits on the day of review
• Strong moderation tooling for community managers
• Rich third-party app ecosystem through the API

• Running a server requires Ruby, PostgreSQL, Redis, Node, and FFmpeg expertise
• Discovery and network effects are weaker than on large centralized platforms
• Moderation and legal duties of a public instance fall on the operator
• AGPL-3.0 requires sharing modifications for network-served forks

Mastodon is free software. There is no official paid plan in the repository; operators of instances may charge or take donations, and self-hosting costs are server, storage, and email.

X is a centralized social platform with a single owner, a huge audience, and algorithmic feeds. Mastodon is a federated network of independently run servers with chronological timelines and community moderation. You gain portability and independence and lose the single massive audience.

• Communities, organizations, and creators that want their own social space
• Users who want to leave a centralized platform
• Developers building on an open social API

• Brands that need the largest possible mass audience
• Teams without sysadmin and moderation capacity
• Anyone who wants an algorithmic discovery feed