Mastodon

Self-hosted microblogging server for running your own community that talks to the rest of the Fediverse over ActivityPub.

50.6k stars, 7.6k forks Ruby On GitHub since February 2016

Visit website View on GitHub How to run it

Mastodon at a glance

Open sourceYes, AGPL-3.0No paid parts in the repository
Health88 of 100Actively developed
Self-hostingDockerOne-click in YunoHost, Unraid and 2 more
Interface75 languagesIncluding English, German and French
Issue repliesWithin ~11 hoursMedian first reply; 100% of recent issues answered

What is Mastodon?

Mastodon is a social network server where people post text, links, pictures and video and follow one another on a chronological timeline that updates live. Each server is independent, yet federates over ActivityPub, so its users can follow and reply to accounts on other Mastodon servers and on different software in the Fediverse. Moderators get reports, blocking, muting, phrase filters, locked accounts and private posts. It acts as an OAuth2 provider with REST and streaming APIs, which third-party apps build on. The stack is Ruby on Rails, PostgreSQL, Redis with Sidekiq, and Node.js for streaming; the interface is translated into 75 languages.

Good fit if

  • You want a Twitter-style community under your own domain and moderation rules.
  • Your members should be able to follow people outside your server instead of living in a closed silo.
  • You need an API that existing mobile and desktop clients already support.

Look elsewhere if

  • You want threaded, topic-based discussions rather than a timeline: Discourse or Flarum.

Before you adopt it

Mastodon is AGPL-3.0, so if you modify it and run it for others you must publish your changes; there are no paid parts in the repository. The repository includes Docker and docker-compose configurations, and an official container image is published. Running a server means looking after PostgreSQL, Redis, Sidekiq workers, media storage and FFmpeg, plus moderating users and federation. Development is steady, with releases in the 4.x series.

Drafted with AI from the project's README and repository data, then checked against that data on 7 November 2026. Report a correction

How to run Mastodon yourself

One-click install

Not listed in Umbrel, TrueNAS, CasaOS and Coolify. Checked against each panel’s app catalog on 12 November 2026.

Ways to install

Docker files
Dockerfile or compose file in the repository
Docker image
ghcr.io/mastodon/mastodon: x86-64, ARM64
Compose file
docker-compose.yml: 5 services (postgres, redis)
Setup effort
3 of 5, judged from the compose file
Kubernetes
No Helm chart in the repository
Packages
AUR, Nix and FreeBSD versions on Repology
Desktop and mobile
No app builds in GitHub releases
Interface languages
75 languages, including English, German, French, Spanish, Portuguese, Dutch, Polish, Russian, Ukrainian and Turkish
Show all 75

Afrikaans, Albanian, Arabic, Aragonese, Armenian, Azerbaijani, Bangla, Basque, Bosnian, Breton, Bulgarian, Catalan, Chinese, Cornish, Corsican, Croatian, Czech, Danish, Dutch, English, Esperanto, Estonian, Faroese, Finnish, French, Galician, Georgian, German, Greek, Hebrew, Hindi, Hungarian, Igbo, Irish, Japanese, Kannada, Kazakh, Korean, Kurdish, Latin, Latvian, Lithuanian, Macedonian, Malay, Malayalam, Marathi, Nepali, Norwegian Nynorsk, Occitan, Persian, Polish, Portuguese, Punjabi, Romanian, Russian, Sanskrit, Sardinian, Scottish Gaelic, Serbian, Sinhala, Slovak, Slovenian, Spanish, Swedish, Tamil, Telugu, Thai, Turkish, Ukrainian, Urdu, Uyghur, Uzbek, Vietnamese, Welsh, Western Frisian

Install instructions: joinmastodon.org or the README on GitHub. Docker images and packages are checked weekly.

Mastodon health: is it still maintained?

88 of 100, actively developed

Release rhythmAlmost dailyLatest: v4.7.5, 3 November 2026
Issue repliesWithin ~11 hoursMedian first reply; 100% of recent issues answered
Bus factorLow riskThe most active of 11 authors wrote 29% of recent commits
  • Activity
    1,016 commits in the last 90 days, the latest on 12 November 2026.
    30 / 30
  • Contributors
    11 people wrote the latest 100 commits; the most active wrote 29% of them.
    14 / 20
  • Releases
    14+ releases in the last 12 months; the latest, v4.7.5, on 3 November 2026.
    19 / 20
  • Replies to issues
    Maintainers answered 100% of recent issues, with a median first reply after 11 hours.
    20 / 20
  • Security practices
    No OpenSSF Scorecard for this repository yet, so this part gets a neutral score.
    5 / 10

Read from GitHub on 12 November 2026. How the score works

Mastodon security

Security advisories are the vulnerabilities the maintainers disclosed on GitHub, with the versions that fix them; many advisories can mean careful disclosure as much as weak code.

Security advisories61 published4 critical, 21 high; 57 list a fixed version

Latest advisories

All 61 advisories on GitHub

Advisories read from GitHub on 12 November 2026.

Mastodon license: is it open source?

Mastodon uses AGPL-3.0, an open-source license approved by the OSI.

  1. February 2016First published on GitHub.
  2. TodayAGPL-3.0.

Mastodon for developers

Written in

  • Ruby 61%
  • TypeScript 23%
  • JavaScript 7%
  • SCSS 5%
  • Haml 4%
  • Other <1%

Getting involved

Good first issues2Open, labelled “fit for beginners”Contributing guideYesCONTRIBUTING.mdOpen issues4,403On GitHub
Authors, 90 days11Of the latest 100 commits
Donations4 waysGitHub Sponsors, own page, Patreon, Open Collective

Language shares are GitHub’s count of the code in the repository.

Alternatives to Mastodon

  • MisskeyA completely free and open interplanetary-microblogging platform 81 health · AGPL-3.0 · 11.4k stars
  • PixelFedPhoto Sharing. For Everyone. 80 health · AGPL-3.0 · 7.1k stars
  • LemmyA decentralised discussion platform for communities. 74 health · AGPL-3.0 · 14.7k stars
  • HumHubHumHub is an Open Source Enterprise Social Network. Easy to install, intuitive to use and extendable with… 81 health · AGPL-3.0 · 6.8k stars
  • DiscourseA platform for community discussion. Free, open, simple. 73 health · GPL-2.0 · 48.1k stars

All 18 projects in Social networks & forums

Questions about Mastodon

Is Mastodon open source?

Yes. Mastodon is published under AGPL-3.0, an OSI-approved open-source license.

Is Mastodon still maintained?

Its health score is 88 of 100 (actively developed). It had 1,016 commits in the last 90 days, the latest on 12 November 2026, and its latest release came out on 3 November 2026.

How do I run Mastodon?

You can run it with the Docker image ghcr.io/mastodon/mastodon and in one click from YunoHost, Unraid, Runtipi and 1 more. The README on GitHub has the exact steps.

What is Mastodon written in?

Mastodon is written mainly in Ruby (61% of the code), with TypeScript (23%) and JavaScript (7%), by GitHub’s count of the repository.

What languages is Mastodon available in?

The repository has interface translations for 75 languages, including English, German, French, Spanish, Portuguese, Dutch, Polish and Russian.

What are the alternatives to Mastodon?

Close alternatives in the Social networks & forums category include Misskey, PixelFed, Lemmy.