Skip to content


Folders and files

Last commit message
Last commit date

Latest commit



GitHub release Ruby Testing Crowdin

Mastodon is a free, open-source social network server based on ActivityPub where users can follow friends and discover new ones. On Mastodon, users can publish anything they want: links, pictures, text, and video. All Mastodon servers are interoperable as a federated network (users on one server can seamlessly communicate with users from another one, including non-Mastodon software that implements ActivityPub!)

Click below to learn more in a video:




No vendor lock-in: Fully interoperable with any conforming platform

It doesn't have to be Mastodon; whatever implements ActivityPub is part of the social network! Learn more

Real-time, chronological timeline updates

Updates of people you're following appear in real-time in the UI via WebSockets. There's a firehose view as well!

Media attachments like images and short videos

Upload and view images and WebM/MP4 videos attached to the updates. Videos with no audio track are treated like GIFs; normal videos loop continuously!

Safety and moderation tools

Mastodon includes private posts, locked accounts, phrase filtering, muting, blocking, and all sorts of other features, along with a reporting and moderation system. Learn more

OAuth2 and a straightforward REST API

Mastodon acts as an OAuth2 provider, so 3rd party apps can use the REST and Streaming APIs. This results in a rich app ecosystem with a lot of choices!


Tech stack

  • Ruby on Rails powers the REST API and other web pages
  • React.js and Redux are used for the dynamic parts of the interface
  • Node.js powers the streaming API


  • PostgreSQL 12+
  • Redis 4+
  • Ruby 3.1+
  • Node.js 18+

The repository includes deployment configurations for Docker and docker-compose as well as specific platforms like Heroku, and Scalingo. For Helm charts, reference the mastodon/chart repository. The standalone installation guide is available in the documentation.



A Vagrant configuration is included for development purposes. To use it, complete the following steps:

  • Install Vagrant and Virtualbox
  • Install the vagrant-hostsupdater plugin: vagrant plugin install vagrant-hostsupdater
  • Run vagrant up
  • Run vagrant ssh -c "cd /vagrant && bin/dev"
  • Open http://mastodon.local in your browser


To set up macOS for native development, complete the following steps:

  • Install Homebrew and run brew install postgresql@14 redis imagemagick libidn nvm to install the required project dependencies
  • Use a Ruby version manager to activate the ruby in .ruby-version and run nvm use to activate the node version from .nvmrc
  • Run the bin/setup script, which will install the required ruby gems and node packages and prepare the database for local development
  • Finally, run the bin/dev script which will launch services via overmind (if installed) or foreman


For production hosting and deployment with Docker, use the Dockerfile and docker-compose.yml in the project root directory.

For local development, install and launch Docker, and run:

docker compose -f .devcontainer/compose.yaml up -d
docker compose -f .devcontainer/compose.yaml exec app bin/setup
docker compose -f .devcontainer/compose.yaml exec app bin/dev

Dev Containers

Within IDEs that support the Development Containers specification, start the "Mastodon on local machine" container from the editor. The necessary docker compose commands to build and setup the container should run automatically. For Visual Studio Code this requires installing the Dev Container extension.

GitHub Codespaces

GitHub Codespaces provides a web-based version of VS Code and a cloud hosted development environment configured with the software needed for this project.

Open in GitHub Codespaces

  • Click the button to create a new codespace, and confirm the options
  • Wait for the environment to build (takes a few minutes)
  • When the editor is ready, run bin/dev in the terminal
  • Wait for an Open in Browser prompt. This will open Mastodon
  • On the Ports tab "stream" setting change Port visibilityPublic


Mastodon is free, open-source software licensed under AGPLv3.

You can open issues for bugs you've found or features you think are missing. You can also submit pull requests to this repository or submit translations using Crowdin. To get started, take a look at If your contributions are accepted into Mastodon, you can request to be paid through our OpenCollective.

IRC channel: #mastodon on


Copyright (C) 2016-2024 Eugen Rochko & other Mastodon contributors (see

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License along with this program. If not, see