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Most of LibCrowds' custom functionality is handled via the core frontend application. However, some functionality such as results analysis, can only be dealt with effectively on the backend server, so we need to install a few additional PYBOSSA plugins. The following page will guide you through the steps required.

Navigate to your PYBOSSA root folder:

cd /path/to/pybossa

If you are running locally, enter the virtual machine:

vagrant ssh

Otherwise, if you're setting up a production server, activate your virtual environement:

source pybossa/env/bin/activate

Now install the various plugins.


This plugin handles the communication with Z39.50 databases that is required to use the platforms Z39.50 task presenter.

Install dependencies:

sudo apt-get install libxml2-dev libxslt-dev python-dev lib32z1-dev

Clone the plugin repo:

git clone pybossa/plugins

Install the plugin and return to root folder:

cd pybossa/plugins/pybossa-z3950
python install
cd ..
cp -r pybossa-z3950/pybossa_z3950 pybossa_z3950
cd /path/to/pybossa


This plugin replaces the default email templates with custom LibCrowds templates.

Clone the plugin repo:

git clone pybossa/plugins

Activate the plugin and return to root folder:

cd pybossa/plugins
cp -r pybossa-lc-email/pybossa_lc_email pybossa_lc_email
cd /path/to/pybossa


This plugin handles various bits of LibCrowds-specific functionality, such as results analysis, generation of Web Annotations and project management via templates.

Clone the plugin repo:

git clone pybossa/plugins

Install the plugin:

cd pybossa/plugins/pybossa-lc
pip install -r requirements.txt
cd ..
cp -r pybossa-lc/pybossa_lc pybossa_lc

The plugins will be available after you restart the server.


Some plugins import Flask modules in a deprecated manner, causing warnings when launching the server. The issue is related to several calls in the files in PyBossa plugins that import Flask submodules in a deprecated manner. These warnings should be patched in a future update, but a temporary fix is obtained with the following:

Flask extension import statements such as

import flask.ext.plugins
should be replaced with
import flask_plugins
Affected files include:

Additionally, the following warning may be observed when calling python

WARNING: Couldn't create 'PyZ3950.PyZ3950_parsetab'. [Errno 20] Not a directory: '/home/vagrant/pybossa-env/lib/python2.7/site-packages/mollyZ3950-2.04_molly1-py2.7-linux-x86_64.egg/PyZ3950/'
<type 'exceptions.ImportError'>
('No module named ext.z3950',)
No module named ext.z3950
Z39.50 plugin disabled
Again, a temporary fix for this is obtained with the following:
pip uninstall mollyZ3950
pip install mollyZ3950-2.04-molly1.tar.gz
pip uninstall Flask-Z3950
pip install Flask-Z3950
in combination with changing flask.ext.* for flask_* in

The next step is Configuring PYBOSSA.