New in version 2.19.

Addons provide ways to customize translation workflow. You can install addons to your translation component and they will work behind the scenes.


Built in addons

Cleanup translation files

Update all translation files to match the monolingual base file. In most file formats this means removing stale translation keys which are no longer present in the base file.

Flag new source strings to need edit

Whenever a new source string is imported from the VCS, it is flagged as needing editing in Weblate. This way you can easily filter and edit source strings written by the developers.

Flag new translations to need edit

Whenever a new translation unit is imported from the VCS, it is flagged as needing editing in Weblate. This way you can easily filter and edit translations created by the developers.

Statistics generator

This addon generates file with detailed information about the translation.

Update ALL_LINGUAS variable in the configure file

Updates the ALL_LINGUAS variable in configure, or files when adding new translation.

Update LINGUAS file

Updates the LINGUAS file when adding new translation.

Generate mo files

Automatically generates mo file for every changed po file.

Update po files to match pot (msgmerge)

Update all po files to match the pot file using msgmerge. This is triggered whenever new changes are pulled from upstream repository.

Formats the Java properties translation

This addon sorts the Java properties file.

Writing addon

You can write own addons as well, all you need to do is subclass BaseAddon, define addon metadata and implement callback which will do the processing.

You can look at example addon for more information:

# -*- coding: utf-8 -*-
# Copyright © 2012 - 2018 Michal Čihař <>
# This file is part of Weblate <>
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <>.

from __future__ import unicode_literals

from django.utils.translation import ugettext_lazy as _

from weblate.addons.base import BaseAddon
from import EVENT_PRE_COMMIT

class ExampleAddon(BaseAddon):
    # Filter for compatible components, every key is
    # matched against property of component
    compat = {
        'file_format': frozenset((
            'po', 'po-unwrapped', 'po-mono', 'po-mono-unwrapped'
    # List of events addon should receive
    events = (EVENT_PRE_COMMIT,)
    # Addon unique identifier
    name = 'weblate.example.example'
    # Verbose name shown in the user interface
    verbose = _('Example addon')
    # Detailed addon description
    description = _('This addon does nothing it is just an example')

    # Callback to implement custom behavior
    def pre_commit(self, translation):