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.
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 |
|
PostgreSQL |
|
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
If you decide to use Celery (giving you asynchronous execution for long-running
tasks), you’ll also 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
andX-Content-Type-Options
,set the
X-Forwarded-For
andX-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, andpass 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!