FOSDEM 2025 – Reflections on the Worlds Largest Open Source Conference

FOSDEM, the Free and Open Source Developers’ European Meeting, is an annual pilgrimage for open-source enthusiasts from all over the world. What started as a small gathering in 2000, originally named the Open Source Developers of Europe Meeting (OSDEM), has grown into one of the most significant conferences dedicated to free and open-source software.

The event was founded by Raphael Bauduin, who wanted to create a space where developers could meet, exchange ideas, and collaborate in person. It quickly gained traction, attracting developers, contributors, and advocates from diverse projects. The conference gained its iconic name when the ‘F’ was added at the request of Richard Stallman, emphasizing the importance of free software.

Location and Growth

Since its inception, FOSDEM has taken place every February in Brussels, Belgium, and has become a massive, volunteer-driven event. It has grown into the largest open-source conference on earth. The Université libre de Bruxelles (ULB) provides the venue, filling its lecture halls, classrooms, and corridors with thousands of attendees.

Each year, the conference expands in scope, featuring new tracks covering a wide range of topics, from programming languages and security to cloud computing and embedded systems. The spirit of collaboration and knowledge sharing remains at the heart of FOSDEM.

25th Anniversary

This year was special, as the 25th anniversary of this extraordinary conference was celebrated. The atmosphere carried both nostalgia for how far the conference has come and excitement for the future of open-source development, which was also reflected in the traditional opening talk.

Core Values

The conference remains free to attend, staying true to its core values of accessibility and community spirit. It continues to be a beacon for those who believe in the power of open collaboration, proving year after year that FOSDEM is not just an event, but a tradition that unites and inspires open-source developers worldwide.

Travel & Parking

Every year, I make the short 90-minute drive to FOSDEM. Driving through the Netherlands and Belgium gives me the flexibility to arrive early and hopefully find a parking spot on the university campus. Registering the car for Belgian emission zones is always a must.

This year, I arrived at 7:30 AM only to find the parking gates still locked. Cars were lining up and blocking traffic. After reaching out to the FOSDEM team without response, a kind university staff member eventually helped us gain access using her university card. Huge thanks to her for saving the morning.

Talks & Events

This year, I attended fewer talks and focused more on socializing. I did not miss the traditional “Welcome to FOSDEM 2025” opening talk, which highlighted the continued growth of the conference and introduced new short-format lightning and lightning-lightning talks.

Other talks included “Ten Years as a Free, Open, and Automated Certificate Authority,” covering the history and future of Let’s Encrypt, and “Immich: Self-hosted photo and video management solution,” which showcased an open-source approach to managing personal media.

BSD Devroom

As a BSD user, the BSD Devroom was my primary focus. The room was well maintained and featured many high-quality talks covering FreeBSD, NetBSD, and related topics. While it was impossible to attend everything, the depth and technical quality were outstanding.

I was able to attend talks such as “Making NetBSD as a fast(er) booting microvm” and “How FreeBSD security audits have improved our security culture,” both of which were particularly insightful.

Socializing

This visit was mainly about socializing, and it was an incredible experience. Reconnecting with old friends, meeting online collaborators in person, and having deep discussions in the BSD Devroom were major highlights.

I also enjoyed talking about my BoxyBSD project and reconnecting with people from the illumos community. Meeting people from Matrix and the Fediverse added even more value to the experience.

Misc

This day also marked Global Switch Day, encouraging people to move from proprietary platforms to open-source alternatives such as Mastodon, Pixelfed, Signal, Matrix, and PeerTube. The message was clear: the future belongs to open and free technology, but only if people take responsibility for their privacy and data.

I also finally bought a fully programmable LED stick that I had previously missed at another conference. It now proudly displays “gyptazy.”

The Bad Things

This year’s FOSDEM was not the best experience for me. The event felt more crowded than ever, with increasing organizational challenges. Many talks required staying in rooms early to avoid being locked out, which was frustrating for many attendees.

The conference also felt more mainstream, with a stronger focus on quantity over deep, technical discussions. Despite this, I want to sincerely thank the staff and volunteers, especially the NOC and VOC teams, for making the event possible.

Looking Ahead

In 2026, I will likely approach FOSDEM the same way: focusing on socializing and meeting people. It was great to see everyone again, and I’m grateful for the experience.