Setting Up Ruby

Mastodon is written in Ruby, and in the next steps, you will create a mastodon user and install the tools to build and set up a Ruby environment. In this environment, you will install and run Mastodon.

Make sure you create the user without password access, so you can only access it via root:

adduser --disabled-login mastodon

Log into the new mastodon user:

su - mastodon

Install the tools to set up the Ruby environment (Listing 2).

git clone https://github.com/rbenv/rbenv.git ~/.rbenv
cd ~/.rbenv && src/configure && make -C src
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
exec bash
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build

Finally, install the correct version of Ruby:

RUBY_CONFIGURE_OPTS=--with-jemalloc rbenv install 3.0.4
rbenv global 3.0.4

You will also need to install Bundler, a package manager for Ruby gems:

gem install bundler --no-document

Configuring PostgreSQL

Exit the mastodon user to go back to root and configure your database manager. Tweak the file located at /etc/postgresql/VERSION NUMBER/main/postgresql.conf to best adapt it to your hardware. Then restart the server with:

systemctl restart postgresql

Next you need to create a database user for your instance, so log into PostgreSQL:

sudo -u postgres psql

And run the following at the psql prompt:

CREATE USER mastodon CREATEDB;

This creates both a mastodon user and a mastodon database associated with the user.

To exit psql type \q and press Enter.

Setting Up Mastodon

To download and install the actual Mastodon code, you again switch to the mastodon user:

su - mastodon

and clone and check out the latest version of the Mastodon server code (Listing 3).

git clone https://github.com/mastodon/mastodon.git live && cd live
git checkout $(git tag -l | grep -v 'rc[0-9]*$' | sort -V | tail -n 1)

Install some more dependencies for Ruby and JavaScript (Listing 4).

bundle config deployment 'true'
bundle config without 'development test'
bundle install -j$(getconf _NPROCESSORS_ONLN)
yarn install --pure-lockfile

And you can now run Mastodon's built-in configuration wizard:

RAILS_ENV=production bundle exec rake mastodon:setup

The configuration wizard will ask you whether you want to run your instance for only one person (supposedly you) or if you will be accepting other users. It will also ask you to provide details about an email address for the maintainers. With this information, the wizard will set up an admin user and give you a one-time, randomly generated password so you can log in.

Note that all the info created by the wizard is stored in a hidden file called .env.production in the top Mastodon directory. You can change any of the values by editing that file.