Data Sovereignty at Scale: How Joomla Powers a Global Community with Mattermost

For more than 21 years, Joomla has been providing one of the world’s most popular content management systems to millions of users around the world. Backed by Open Source Matters, Inc., a nonprofit organization that provides organizational, legal, and financial support for the project, Joomla is built and maintained by a community of developers, designers, site builders, and open source enthusiasts committed to the long-term health and sustainability of the project. Powered by a team of over 1,500 volunteers, Joomla is used by more than 2 million websites globally.

Looking for a transparent, secure collaboration platform offering data sovereignty

To build Joomla, contributors from around the world need centralized collaboration tools that enable team members to stay aligned and move work forward. In 2022, Joomla began looking to replace its existing messaging tool, Glip, as part of a broader move toward greater control over its own infrastructure.

“This was part of a strategic push for greater openness and alignment with our open source values,” says Emmanuel Lemor, Vice President at Open Source Matters. “Glip had limitations around transparency and access. For us, the ability to have full control over our collaboration infrastructure is non-negotiable.” 

Choosing Mattermost for data sovereignty, control, and privacy

While looking for a Glip replacement, Joomla found Mattermost, the secure collaboration platform built for data sovereignty, operational resilience, and control. Seeing an alignment between Mattermost and Joomla’s values, the team quickly recognized it as the right fit, switched over, and hasn’t looked back since.

“Our community is vast and global, and Mattermost has become the daily communication backbone for nearly all of our official teams and working groups,” Lemor continues. “Mattermost is the central hub where the entire project collaborates, hosting a vast and expanding array of specialized public and private channels.”

Those channels are dedicated to all sorts of topics, working groups, and project initiatives — from Bug Squad, Marketing, and SEO to Google Summer of Code.

“Mattermost allows us to decide who has access to what, knowing we want the majority of communication to happen in open channels for transparency’s sake. Permissions management was previously a major friction point,” Lemor explains. “A key goal of our move was to make our community more open and transparent. With Mattermost, we are able to open up all non-sensitive channels to the public, allowing anyone to see how Joomla is built and how decisions are made.” 

Even as Joomla extends more of its work to the public, the project remains just as focused on protecting what needs to stay private.

“While embracing openness, we also prioritize privacy,” says Carlos Cámara, Operations Department Coordinator at Open Source Matters. “Mattermost’s architecture ensures that private chats remain private, and that we can manage personal data in compliance with GDPR and other regulations. We use our own identity provider solution that is fully integrated with Mattermost, which allows us to offer a fully GDPR-compliant solution while repeating our volunteers’ privacy.” 

Streamlining day-to-day collaboration with Mattermost

The Joomla team primarily uses Mattermost for real-time, channel-based communication.

“Channels are crucial for organizing our community, which involves so many different teams and projects,” Lemor says. “They allow for focused, topic-specific decisions. A public channel like the ‘Joomla Improvers’ space has been instrumental in fostering our commitment to a safe and supportive environment, where members can ask questions without fear of shaming.” 

The community is also drawn to Mattermost’s mobile and desktop access, which enables contributors to stay connected and responsive from anywhere. They also heavily use Mattermost’s file sharing and search features, which make it easy to share and surface screenshots, design mockups, and code snippets. 

“With dozens of active channels and thousands of messages, the ability to search across all channels is essential,” Lemor says. “Whether a developer is looking for a discussion about a specific pull request, a marketing volunteer needs to find a previously shared graphic, or a new joiner is searching for onboarding instructions, the global search feature saves hours of digging. It ensures that knowledge shared anywhere in the community remains discoverable.” 

Streamlining voice and video collaboration with Mattermost Calls

With a team spread out across the world in dozens of time zones, Mattermost Calls has also made a huge impact.

“Being able to jump into an instant audio or video call without scheduling a separate Zoom or Google Meet session is a massive productivity boost,” Lemor explains. “Our teams occasionally use Mattermost Calls for quick sessions. Because the calls are native to the platform, we don’t lose context. Everything stays logged and searchable in the channel for anyone who couldn’t attend live.”

Preserving organizational history with archived channels

As a long-running open source project, Joomla generates a slew of temporary and time-bound channels — think specific release cycles, Google Summer of Code projects, and working groups that have completed their mandate.

“The ability to archive channels rather than deleting them is invaluable,” Cámara says. “Archived channels preserve the entire conversation history and decision trail for future reference, audits, or onboarding new members who need to understand past discussions.”

Archiving channels also keeps Joomla’s active channel list clean and focused, reducing noise and sharpening focus for current volunteers.

“When a similar initiative arises months or years later, we can easily unarchive or search within the old channel to avoid reinventing the wheel,” Cámara adds. 

Joomla also appreciates the ability to configure their own emoticons, which makes the project’s digital workspace “feel more like a home.” As an example, the team added a Joomla heart emoticon which community members use very often to show appreciation and celebrate contributions.

“This might seem small, but it has become a powerful tool for building community identity and morale,” Lemor says.

Improving project management with Boards

Joomla is exploring Boards, a kanban-style project management tool inside Mattermost, which they believe will be a “game-changer” for project management.

“Currently, many teams juggle tasks across GitHub Projects, spreadsheets, or other external tools,” Cámara says. 

With Boards, the team believes they could manage Joomla Academy and Google Summer of Code projects more effectively, streamline feature development, coordinate department initiatives more effectively, and centralize task management.

“Our goal is to introduce structured workflows by asking team leaders to adopt Boards for their team’s task tracking and then layer Playbooks on top for the repeatable checklists within those tasks,” Lemor says. “We are optimistic this combined approach will unlock the process automation benefits we envision.” 

Exploring AI safely and securely

Joomla is in the process of building an internal AI framework that will outline how the organization can use AI. The team organizes all related work on this initiative in a channel called Joomla AI Framework Working Group, which serves as the primary channel for daily updates, code reviews, and debugging sessions.

“It’s the central nervous system where mentors share architectural insights, contributors ask questions, and the team builds a shared understanding of the project goals,” Cámara says. “While the final code lives in GitHub, the collaborative spark that drives it forward happens in Mattermost.” 

Once the framework is finalized, Joomla sees several valuable use cases for AI in Mattermost:

• Automated triage: an AI assistant that can help triage support requests, directing users to the correct documentation and escalating complex issues to experts
• Community moderation: AI flagging potentially harmful or toxic language in real time, allowing moderators to intervene faster 
• How-to assistance: a Joomla-specific AI bot trained on the project’s documentation and community forums that could answer common questions, guide users through configurations, and even generate boilerplate code for extensions
• Meeting summarization: a bot that automatically joins team meetings and generates concise summaries of key decisions and action items

“We look forward to seeing AI capabilities in a privacy-respecting, open-source way, which is the logical next step for Mattermost and could be a powerful tool for the Joomla community,” Lemor concludes.