Installation

This guide will help you to install pretalx on Linux. This setup is suitable to support events in usual sizes, but the guide does not go into performance tuning or customisation options beyond the standard settings.

Warning

While we try to make it straightforward to run pretalx, it still requires some Linux experience to get it right, particularly to make sure that standard security practices are followed. If you’re not feeling comfortable managing a Linux server, check out our hosting and service offers at pretalx.com.

For the more automation-savvy, we also provide an Ansible role that follows this guide. If you prefer a docker setup, there is a docker-compose setup. Please note that the docker setup is community provided and not officially supported.

Step 0: Prerequisites

Please set up the following systems beforehand. We can’t go into their use and configuration here, but please have a look at the linked pages.

  • Python 3.10 or newer

  • An SMTP server to send out mails

  • An HTTP reverse proxy like nginx to allow HTTPS connections and serve files from the filesystem

  • A database server: PostgreSQL 13+, or SQLite 3. Given the choice, we’d recommend to use PostgreSQL.

  • A redis server, if you want to use pretalx with an asynchronous task runner or improved caching.

  • nodejs and npm (usually bundled with nodejs). You’ll need a supported version of nodejs.

Please ensure that the environment used to run pretalx is configured to work with non-ASCII file names. You can check this by running:

$ python -c "import sys; print(sys.getfilesystemencoding())"
utf-8

Step 1: Unix user

Hint

All code lines prepended with a # symbol are commands that you need to execute on your server as the root user (e.g. using sudo); you should run all lines prepended with a $ symbol as the pretalx user. If the prompt reads (env)$, your virtual Python environment should be active.

As we do not want to run pretalx as root, we first create a new unprivileged user:

# adduser pretalx --disabled-password --home /var/pretalx

Step 2: Database setup

pretalx runs with PostgreSQL or SQLite. If you’re using SQLite, you can skip this step, as there is no need to set up the database.

We recommend using PostgreSQL. This is how you can set up a database for your pretalx installation – if you do not use PostgreSQL, please refer to the appropriate documentation on how to set up a database:

# sudo -u postgres createuser pretalx -P
# sudo -u postgres createdb -O pretalx pretalx

Make sure that your database encoding is UTF-8. You can check with this command:

# sudo -u postgres psql -c 'SHOW SERVER_ENCODING'

Step 3: Package dependencies

Besides the packages above, you might need local system packages to build and run pretalx. We cannot maintain an up-to-date dependency list for all Linux flavours – on Ubuntu-like systems, you will need packages like:

  • build-essential

  • libssl-dev

  • python3-dev

  • python3-venv

  • gettext

Step 4: Configuration

Now we’ll create a configuration directory and configuration file for pretalx:

# mkdir /etc/pretalx
# touch /etc/pretalx/pretalx.cfg
# chown -R pretalx:pretalx /etc/pretalx/
# chmod 0600 /etc/pretalx/pretalx.cfg

This snippet can get you started with a basic configuration in your /etc/pretalx/pretalx.cfg file:

# This is an example pretalx configuration file.
# Documentation: https://docs.pretalx.org/administrator/configure.html

[filesystem]
data = /var/pretalx/data
static = /var/pretalx/static

[site]
debug = False
url = https://pretalx.mydomain.com

[database]
backend = postgresql
name = pretalx
user = pretalx
# For PostgreSQL on the same host, we don't need one because we can use
# peer authentification if our PostgreSQL user matches our unix user.
password = Change this in production or you're going to have a bad time
# For a remote host, supply an IP address
# For local postgres authentication, you can leave the host empty
host = localhost
port = 5432

[mail]
from = admin@localhost
host = localhost
port = 25
user = admin
password = Change this in production or you're going to have a bad time
tls = False
ssl = True

Refer to Configuration for a full list of configuration options – the options above are only the ones you’ll likely need to get started.

Step 5: Installation

For your Python installation, you’ll want to use a virtual environment to isolate the installation from system packages. Set up your virtual environment like this – you’ll only have to run this command once (that is, only once per Python version – when you upgrade from Python 3.13 to 3.14, you’ll need to remove the old venv directory and create it again the same way):

$ python3 -m venv /var/pretalx/venv

Now, activate the virtual environment – you’ll have to run this command once per session whenever you’re interacting with python, pip or pretalx:

$ source /var/pretalx/venv/bin/activate

Now, upgrade your pip and then install the required Python packages:

(venv)$ pip install -U pip setuptools wheel gunicorn

Note

You may need to replace all following mentions of pip with pip3.

Database

Command

SQLite

pip install --upgrade-strategy eager -U pretalx

PostgreSQL

pip install --upgrade-strategy eager -U "pretalx[postgres]"

If you intend to run pretalx with asynchronous task runners or with redis as cache server, you can add [redis] to the installation command, which will pull in the appropriate dependencies. Please note that you should also use pretalx[redis] when you upgrade pretalx in this case.

We also need to create a data directory:

$ mkdir -p /var/pretalx/data/media

We compile static files and translation data and create the database structure:

(venv)$ python -m pretalx migrate
(venv)$ python -m pretalx rebuild

Now, create a user with administrator rights, an organiser and a team by running:

(venv)$ python -m pretalx init

Step 6: Starting pretalx as a service

We recommend starting pretalx using systemd to make sure it starts up after a reboot. Create a file named /etc/systemd/system/pretalx-web.service, and adjust the content to fit your system:

[Unit]
Description=pretalx web service
After=network.target

[Service]
User=pretalx
Group=pretalx
WorkingDirectory=/var/pretalx
ExecStart=/var/pretalx/venv/bin/gunicorn pretalx.wsgi \
                      --name pretalx --workers 4 \
                      --max-requests 1200  --max-requests-jitter 50 \
                      --log-level=info --bind=127.0.0.1:8345
Restart=on-failure

[Install]
WantedBy=multi-user.target

pretalx optionally runs with Celery, a service that allows for long-running tasks (like sending many emails) to be performed asynchronously in the background. We strongly recommend running pretalx with Celery workers, as some things, like cleaning up unused files, are otherwise not going to work.

To run Celery workers, you’ll need a second service /etc/systemd/system/pretalx-worker.service with the following content:

[Unit]
Description=pretalx background worker
After=network.target

[Service]
User=pretalx
Group=pretalx
WorkingDirectory=/var/pretalx
ExecStart=/var/pretalx/venv/bin/celery -A pretalx.celery_app worker -l info
Restart=on-failure

[Install]
WantedBy=multi-user.target

You can now run the following commands to enable and start the services:

# systemctl daemon-reload
# systemctl enable pretalx-web pretalx-worker
# systemctl start pretalx-web pretalx-worker

Step 7: Reverse proxy

You’ll need to set up an HTTP reverse proxy to handle HTTPS connections. It does not particularly matter which one you use, as long as you make sure to use strong encryption settings. Your proxy should

  • serve all requests exclusively over HTTPS,

  • follow established security practices regarding protocols and ciphers.

  • optionally set best-practice headers like Referrer-Policy and X-Content-Type-Options,

  • set the X-Forwarded-For and X-Forwarded-Proto headers,

  • set the Host header,

  • serve all requests for the /static/ and /media/ paths from the directories you set up in the previous step, without permitting directory listings or traversal. Files in the /media/ directory should be served as attachments. You can use fairly aggressive cache settings for these URLs, and

  • pass all other requests to the gunicorn server you set up in the previous step.

Step 8: Check the installation

You can make sure the web interface is up and look for any issues with:

# journalctl -u pretalx-web

If you use Celery, you can do the same for the worker processes (for example in case the emails are not sent):

# journalctl -u pretalx-worker

If you’re looking for errors, check the pretalx log. You can find the logging directory in the start-up output.

Once pretalx is up and running, you can also find up to date administrator information at https://pretalx.yourdomain.com/orga/admin/.

Step 9: Provide periodic tasks

There are a couple of things in pretalx that should be run periodically. It does not matter how you run them, so you can go with your choice of periodic tasks, be they systemd timers, cron, or something else entirely.

In the same environment as you ran the previous pretalx commands (e.g. the pretalx user, using either the executable paths in the /var/pretalx/venv directory, or running /var/pretalx/venv/bin/activate first), you should run

  • python -m pretalx runperiodic somewhere every five minutes and once per hour.

  • python -m pretalx clearsessions about once a month.

You could for example configure the pretalx user cron like this:

*/10 * * * * /var/pretalx/venv/bin/python -m pretalx runperiodic

Next Steps

You made it! You should now be able to reach pretalx at https://pretalx.yourdomain.com/orga/ Log in with the administrator account you configured above, and create your first event!

Check out Configuration for details on the available configuration options.

If you want to read about updates, backups, and monitoring, head over to our Maintenance documentation!