Installing Flectra

There are multiple ways to install Flectra, or not install it at all, depending on the intended use case.

This documents attempts to describe most of the installation options.


The easiest way to use Flectra in production or to try it.

Packaged installers

Suitable for testing Flectra, developing modules and can be used for long-term production use with additional deployment and maintenance work.

Source install

Provides greater flexibility: e.g. allow multiple running Flectra versions on the same system. Good for developing modules, can be used as base for production deployment.


If you usually use docker for development or deployment, an official docker base image is available.


There are two different Editions of Flectra: the Community and Professional versions. Using the Professional version is possible on Flectra Online and accessing the code is restricted to Professional customers and partners. The Community version is freely available to anyone.



To simply get a quick idea of Flectra, demo instances are available. They are shared instances which only live for a few hours, and can be used to browse around and try things out with no commitment.

Demo instances require no local installation, just a web browser.

Flectra Online

Trivial to start with, fully managed and migrated by Flectra S.A., Flectra Online provides private instances and starts out free. It can be used to discover and test Flectra and do non-code customizations (i.e. incompatible with custom modules or the Flectra Apps Store) without having to install it locally.

Can be used for both testing Flectra and long-term production use.

Like demo instances, Flectra Online instances require no local installation, a web browser is sufficient.

Packaged installers

Flectra provides packaged installers for Windows, deb-based distributions (Debian, Ubuntu, …) and RPM-based distributions (Fedora, CentOS, RHEL, …) for both the Community and Professional versions.

These packages automatically set up all dependencies (for the Community version), but may be difficult to keep up-to-date.

Official Community packages with all relevant dependency requirements are available on our nightly server. Both Community and Professional packages can be downloaded from our download page (you must to be logged in as a paying customer or partner to download the Professional packages).


  1. Download the installer from our nightly server (Community only) or the Windows installer from the download page (any edition).

  2. Execute the downloaded file.


    On Windows 8 and later you may see a warning titled “Windows protected your PC”.
    Click on More Info and then on Run anyway.
  3. Accept the UAC prompt.

  4. Go through the various installation steps.

Flectra will automatically be started at the end of the installation.



Flectra needs a PostgreSQL server to run properly. The default configuration for the Flectra ‘deb’ package is to use the PostgreSQL server on the same host as your Flectra instance. Execute the following command in order to install the PostgreSQL server:

$ sudo apt install postgresql -y


Flectra S.A. provides a repository that can be used with Debian and Ubuntu distributions. It can be used to install Flectra Community Edition by executing the following commands:

$ wget -q -O - | sudo gpg --dearmor -o /usr/share/keyrings/flectra-archive-keyring.gpg
$ echo 'deb [signed-by=/usr/share/keyrings/flectra-archive-keyring.gpg] ./' | sudo tee /etc/apt/sources.list.d/flectra.list
$ sudo apt-get update && sudo apt-get install flectra

You can then use the usual apt-get upgrade command to keep your installation up-to-date.


At this moment, there is no nightly repository for the Professional Edition.

Distribution package

Instead of using the repository as described above, the ‘deb’ packages for both the Community and Professional editions can be downloaded from the official download page.


Flectra 3 ‘deb’ package currently supports Debian 11 (Bullseye), Ubuntu 22.04 (Jammy) or above.

Next, execute the following commands as root:

# dpkg -i <path_to_installation_package> # this probably fails with missing dependencies
# apt-get install -f # should install the missing dependencies
# dpkg -i <path_to_installation_package>

This will install Flectra as a service, create the necessary PostgreSQL user and automatically start the server.


  • The python3-xlwt Debian package does not exists in Debian Buster nor Ubuntu 18.04. This python module is needed to export into xls format.

    If you need the feature, you can install it manually with:

    $ sudo pip3 install xlwt
  • The num2words python package does not exists in Debian Buster nor Ubuntu 18.04. Textual amounts will not be rendered by Flectra and this could cause problems with the l10n_mx_edi module.

    If you need this feature, you can install manually with:

    $ sudo pip3 install num2words

Source install

The source “installation” is really about not installing Flectra, and running it directly from source instead.

It can be more convenient for module developers as the Flectra source is more easily accessible than using packaged installation.

It also makes starting and stopping Flectra more flexible and explicit than the services set up by the packaged installations, and allows overriding settings using command-line parameters without needing to edit a configuration file.

Finally it provides greater control over the system’s set up, and allows to more easily keep (and run) multiple versions of Flectra side-by-side.

Fetch the sources

There are two ways to obtain the source code of Flectra: as a zip archive or through git.


Community Edition:


The following requires Git to be installed on your machine and that you have basic knowledge of Git commands. To clone a Git repository, you must choose between cloning with HTTPS or SSH. If you do not know the difference between the two, the best option is most likely HTTPS. If you are following the Getting started developer tutorial, or plan on contributing to Flectra source code, choose SSH.


The Professional Git repository does not contain the full Flectra source code. It is only a collection of extra add-ons. The main server code is in the Community version. Running the Professional version actually means running the server from the Community version with the addons-path option set to the folder with the Professional version. You need to clone both the Community and Professional repository to have a working Flectra Professional installation. See Editions to get access to the Professional repository.

C:\> git clone


The Professional git repository does not contain the full Flectra source code. It is only a collection of extra add-ons. The main server code is in the Community version. Running the Professional version actually means running the server from the Community version with the addons-path option set to the folder with the Professional version. You need to clone both the Community and Professional repository to have a working Flectra Professional installation.



Flectra requires Python 3.7 or later to run. Visit Python’s download page to download and install the latest version of Python 3 on your machine.

During installation, check Add Python 3 to PATH, then click Customize Installation and make sure that pip is checked.


If Python 3 is already installed, make sure that the version is 3.7 or above, as previous versions are not compatible with Flectra.

C:\> python --version

Verify also that pip is installed for this version.

C:\> pip --version


Flectra uses PostgreSQL as database management system. Download and install PostgreSQL (supported version: 12.0 and later).

By default, the only user is postgres but Flectra forbids connecting as postgres, so you need to create a new PostgreSQL user:

  1. Add PostgreSQL’s bin directory (by default: C:\Program Files\PostgreSQL\<version>\bin) to your PATH.

  2. Create a postgres user with a password using the pg admin gui:

    1. Open pgAdmin.

    2. Double-click the server to create a connection.

    3. Select Object ‣ Create ‣ Login/Group Role.

    4. Enter the username in the Role Name field (e.g. flectra).

    5. Open the Definition tab and enter the password (e.g. flectra), then click Save.

    6. Open the Privileges tab and switch Can login? to Yes and Create database? to Yes.


Before installing the dependencies, you must download and install the Build Tools for Visual Studio. When prompted, select C++ build tools in the Workloads tab and install them.

Flectra dependencies are listed in the requirements.txt file located at the root of the Flectra community directory.


It can be preferable to not mix python modules packages between different instances of Flectra or with your system. You can use virtualenv to create isolated Python environments.

Navigate to the path of your Flectra Community installation (CommunityPath) and run pip on the requirements file in a terminal with Administrator privileges:

C:\> cd \CommunityPath
C:\> pip install setuptools wheel
C:\> pip install -r requirements.txt

For languages with right-to-left interface (such as Arabic or Hebrew), the package rtlcss is needed:

  1. Download and install nodejs.

  2. Install rtlcss:

    C:\> npm install -g rtlcss
  3. Edit the System Environment’s variable PATH to add the folder where rtlcss.cmd is located (typically: C:\Users\<user>\AppData\Roaming\npm\).


wkhtmltopdf is not installed through pip and must be installed manually in version 0.12.5 for it to support headers and footers. See our wiki for more details on the various versions.

Running Flectra

Once all dependencies are set up, Flectra can be launched by running flectra-bin, the command-line interface of the server. It is located at the root of the Flectra Community directory.

To configure the server, you can either specify command-line arguments or a configuration file.


For the Professional edition, you must add the path to the professional addons to the addons-path argument. Note that it must come before the other paths in addons-path for addons to be loaded correctly.

Common necessary configurations are:

  • PostgreSQL user and password.

  • Custom addon paths beyond the defaults, to load your own modules.

A typical way to run the server would be:

C:\> cd CommunityPath/
C:\> python flectra-bin -r dbuser -w dbpassword --addons-path=addons -d mydb

Where CommunityPath is the path of the Flectra Community installation, dbuser is the PostgreSQL login, dbpassword is the PostgreSQL password, and mydb is the name of the PostgreSQL database.

After the server has started (the INFO log flectra.modules.loading: Modules loaded. is printed), open http://localhost:8069 in your web browser and log in with the base administrator account: Use admin for the Email and, again, admin for the Password. That’s it, you just logged into your own Flectra database!


  • From there, you can create and manage new users.

  • The user account you use to log into Flectra’s web interface differs from the --db_user CLI argument.


The full documentation on how to use Flectra with Docker can be found on the official Flectra docker image page.