Fosdem 2026

2026-02-02

FOSDEM 2026 Experience

I’m on my way to Brussels Airport after spending an amazing weekend at FOSDEM. I'm full of enthusiasm and appreciation for the community, but I also feel a urge to dedicate some time to help the projects I use. A good measure of success would be doing something worth sharing and hopefully becoming a speaker next year.

First Impressions

When I visited FOSDEM for the first time last year, I had no idea what to expect. However, when my good friend Karel, a true believer in open-source, mentioned it, I did not hesitate—though I actually not remember if I hesitated. As last year turned out to be an incredible experience, which made attending this year a definite plan.

The Journey to Brussels

Once again, catching planes proved to be not my strong suit. I had planned to be at Arlanda (Stockholm Airport) 45 minutes before boarding, but an accident on the train track delayed everything. Installing Uber, creating an account, and taking a taxi ride to the airport turned an ordinary journey into a scene from an action movie.

I arrived just nine minutes before boarding at Terminal 5. Thus began the challenge: how fast could I get from the front door to gate D14? It took me just under ten minutes, speeding at about 15 km/h on straight paths, maneuvering through security, and convincing the guard that my plane was leaving in four minutes and that my green backpack needed to be prioritized.

Once aboard, my heart rate began to settle. After an hour's flight and a short nap to recharge, I started drafting my plan for the conference using the dedicated FOSDEM app. When the man sitting next to me asked, "FOSDEM?", it was clear that the question was directed at me. After a brief conversation, I discovered that he was one of the speakers and that he deals with the specification of technologies that must be used in telecommunications in order to meet certain requirements of the cyber resilience act (CRA). Since he knew nothing about confidential computing, I had the opportunity to share with him the knowledge I had gained over the past year.

Arriving in Brussels

Upon arriving at Zaventem (Brussels Airport), finding the right bus was quite a challenge. Note to self: bus 12 goes directly from the airport to the city center (Trone). Additionally, Brussels takes bilingualism to another level; the same bus stop can have different names in French and Dutch, making it impossible to make the connection if you don't know both languages.

Meeting my friends who had already arrived, we walked around the city, marveling at the Cathedral of St. Michael and St. Gudula, home to the famous Brussels falcons. Sara (my friend living in Brussels) showed us the best spots in the city, including a rooftop bar where we simply enjoyed the view. We observed the Palais de Justice and learned about its reconstruction, which has taken over 50 years. We also visited (read the following word with a strong French accent in your head to get the right feel) Grand-Place and strolled through the northern part of the center. We ended up at a small bar, enjoying a view of the city hall of Ixelles. During our conversations, Karel raised the topic of cleanroom rewriting of code, and this led us to attend a lecture the next day. Stay tuned!

FOSDEM: Saturday

The next morning, we met at Université Libre Bruxelles to kick off FOSDEM. I attended several talks on code signing and build reproducibility, followed by discussions on containers—a very popular topic this year.

Afterward, I moved to the Modern Email room to check out Stalwart. Keep in mind that getting into popular talks requires proper planning; without it, you may find yourself unable to enter if the room fills up. I enjoyed a captivating presentation about JMAP for not just mail but also calendars and contacts. The talk was excellent from a presentational standpoint, and you can check it out here. Following that was a discussion on Stalwart as the advanced open-source email solution aspiring to be able to reach the maturity of Google. I have a similar feeling about Stalwart as I do about Bitwarden; even though both are backed by companies, their open-source versions are very suitable for home use.

I felt a bit lazy to head to another building, so I dropped into the next room and observed an interesting software solution: a probabilistic turn-by-turn public transport planner. You can find that here, and the source code seems to be available here.

After a full day of lectures, we participated in a historical walkthrough that raised important questions about implementing all open-source software under more permissive licenses.

During the day, I also learned about XMPP bridges (see more at codeberg.org/slidge/slidge). This seems like the ideal solution for users of multiple apps who don't want to install yet another. Setting up a WhatsApp bridge appears to be the logical next step, and I hope this may help me to convince myself and encourage others to transition to XMPP.

That evening, we returned to our accommodation and coding/devops evening. I fixed the JMAP on my Stalwart deployment. As a reference, when using Stalwart, the JMAP URL must contain /jmap/sessions.

FOSDEM: Sunday

After an information-packed Saturday, I attended the Confidential Computing room, which I had eagerly anticipated. This topic has been close to my heart since exploring it as a thesis and later as a job. The first talk featured Coconut-SVSM from Joerg, a project I forked and updated for a Proof-of-Concept in my thesis. Afterward, I approached Joerg about the progress on live migration—related to my thesis work. There is still much debate surrounding the migration of AMD SEV-SNP, and the migration of TDX is not yet on the agenda.

The second talk focused on restarting confidential virtual machines, aimed at allowing users to bring their firmware. Then, we delved into a block of discussions about attestations.

In the afternoon, I revisited XMPP. I discovered clients striving to support stories and subscribers, transforming XMPP into a full-fledged social network. The event wrapped up with a final talk on Open Source and AI, after which we helped clean up the main venue.

Our next goal was to visit the Atomium. In the middle of winter, at night, and amidst the rain (which came later), the Atomium looked beautiful—no tourists and splendidly lit. We then walked back to the city center to soak in the atmosphere of Brussels.

Tips for my future self: Take a paper and pen to jot down questions during presentations and remind yourself what to check in the days that follow.