FOSDEM 2025, one of the largest open-source conferences globally, concluded last week, featuring an array of talks, workshops, and community events. Held annually in Brussels, Belgium, FOSDEM gathers developers, contributors, and enthusiasts from around the world to explore the latest trends, projects, and innovations in the open-source ecosystem.

Having missed the in-person event in 2024 due to my relocation to London, I was excited to attend FOSDEM 2025 in person and reconnect with the vibrant open-source community. This year, I boarded the Eurostar from London to Brussels, eager to engage with fellow contributors, maintainers, and developers.

The OKD Meetup @ CentOS Connect⌗

My FOSDEM experience kicked off at the OKD Meetup during CentOS Connect on Thursday. OKD, the Origin Community Distribution of Kubernetes, has undergone significant architectural and governance changes over the past year, making it a major discussion point among OpenShift and Kubernetes enthusiasts.

Historically, OKD has been a community-driven project built from the upstream OpenShift codebase, tailoring a Kubernetes distribution based on Fedora CoreOS. The project is now transitioning to CentOS Stream CoreOS and using CentOS Stream base images instead of UBI1. While this shift has slowed the release cycle, it aims to provide a more sustainable and community-led project aligned with Fedora, CentOS, and upstream Kubernetes releases while anticipating the next versions and features of the enterprise OpenShift product.

A key challenge is migrating existing boot images—still Fedora-based—to CentOS Stream CoreOS images with container-native layering to provide essential tools and services for OKD cluster bootstrapping. The meetup was an excellent opportunity to discuss these developments, the challenges faced by maintainers, and upcoming roadmap priorities. Community feedback on expectations and use cases for OKD was also invaluable.

A particularly interesting discussion involved the University College of London (UCL) and their use of OKD to provide a Kubernetes platform for students and researchers. Their focus on virtual machine provisioning via KubeVirt simplifies workload isolation in shared, multi-tenant environments, integrating with OpenStack infrastructure for persistent storage and networking services.

I could meet with GingerGeek, who is contributing the community operators catalog for OKD. He shared insights on the challenges of maintaining operators across multiple Kubernetes versions and the need for a more streamlined operator releasing process. We discussed the potential for moving to Konflux as a unified operator releasing platform, enabling developers to build, test, and deploy operators across OKD and Openshift, including Multi-architecture builds.

Later, Ausil presented efforts to enhance the developer and community experience, improve Kubernetes ecosystem integration, and align OKD with CentOS Stream CoreOS and CNCF projects. The goal is to make OKD a full upstream of OpenShift, fostering a more open and transparent development process driven by community needs.

Scheduling in OKD and Kubernetes⌗

I also delivered a talk on scheduling in OKD and Kubernetes, focusing on the potential unlocked by Scheduling Readiness Gates in recent Kubernetes versions. This talk was inspired by the two-level scheduling architecture of the Mesos project and work we did at Red Hat with the Multiarch Tuning Operator.

While the audience varied in familiarity with Kubernetes scheduler internals, the discussion sparked interest on the scheduling challenges in multi-tenant environments, advanced scheduling policies, and the potential for automated optimization of scheduling decisions.

I plan to share more details on improving scheduling in Kubernetes and OKD in a future blog post and paper we are currently writing. Our vision is to integrate Scheduling Readiness Gates with distributed controllers, enabling researchers and Site Reliability Engineers to define custom scheduling policies rather than relying on monolithic, forked scheduler extensions.

Being back at a conference and speaking, despite shy especially in a foreign language, to an audience of experts and enthusiasts was a challenging yet rewarding experience. You can find the recording of my talk on the CentOS Connect recordings.

FOSDEM 2025 Highlights⌗

The main FOSDEM event on Saturday and Sunday was a whirlwind of activity, with multiple tracks covering topics ranging from cloud-native technologies to open-source databases, programming languages, and governance. Of course, there were also key discussions on Linux kernel development and AI’s role in the open-source ecosystem.

The scale of FOSDEM continues to grow, reflecting increasing enthusiasm for open-source projects. In 2024, the event featured 948 speakers, 875 events, and 67 tracks. In 2025, these numbers grew to 1,193 speakers, 1,104 events, and 79 tracks, underscoring the community’s expanding engagement and the broadening scope of FOSS topics.

Notable Sessions⌗

  • Containers Devroom: Adrian Reber’s talk on the state of Checkpoint/Restore in Kubernetes covered challenges in live container migration and ongoing efforts to integrate checkpointing with Kubernetes schedulers and CRI-O. I’m looking forward to read his KEP and perhaps contribute to the multi-architecture aspects of this feature.
  • Open Research: JOSSCast: Experimenting with Storytelling in Open Research highlighted the importance of storytelling in engaging audiences and fostering collaboration between the FOSS and Open Research communities.
  • AI and Engineering Devroom: Discussions on Large-Language Models (LLMs) provided insights into cutting-edge AI trends. While informative, I would have appreciated more focus on ethical and societal implications, as well as other AI methodologies beyond LLMs.
  • Sustainability in Kubernetes: The session on Kubernetes Emissions Insights tackled the environmental impact of cloud-native technologies, emphasizing resource optimization and sustainable cluster management. As I plan my contributions to Kubernetes SIGs after earning the contributor membership, the sustainability discussion particularly resonated with me. The insights will be valuable for refining scheduling, autoscaling, and descheduling strategies to optimize Kubernetes workloads and minimize the environmental impact of cloud-native deployments.

Community Protest at FOSDEM 2025⌗

This year’s FOSDEM was not without controversy. A protest emerged over the participation of Jack Dorsey (former Twitter CEO) in the open-source ecosystem. The backlash quickly gained traction in blog posts and social media, leading to the cancellation of Dorsey’s keynotes. The incident highlighted ongoing tensions between corporate interests and the open-source community’s grassroots ethos, reaffirming the need to safeguard FOSS as a space for open collaboration, free from undue corporate influence. Despite no official response from the organizers, in a world threatened by the far right movements and the rise of authoritarianism, protectionism and funding to the defense systems, the open-source community has given an example of how people can influence the direction of the world around them by standing up for their cause. The open-source community must remain vigilant in upholding its values of transparency, inclusivity, and democratic governance, in the digital world and in the streets to build a better world for the future generations.

People shouldn’t be afraid of their government. Governments should be afraid of their people. Alan Moore, V for Vendetta

Bars and Restaurants in Brussels⌗

Beyond the conference, I had the chance to explore some fantastic spots in Brussels:

  • Delirium Café: An essential stop for beer lovers, offering an extensive selection of local and international brews.
  • La Machine: A cozy bar with a great Belgian beer selection and a welcoming atmosphere.
  • H&Ks: A vibrant cocktail bar with live music.
  • Kiosk Radio: A left-leaning community-driven radio station and bar featuring local artists.

Final Thoughts⌗

FOSDEM 2025 was an unforgettable experience. The opportunity to engage with passionate developers, contribute to discussions on open-source sustainability, and deliver my own talk made it especially rewarding. As the FOSS ecosystem continues to grow, it’s inspiring to see the community driving meaningful change through collaboration and innovation.

I look forward to staying involved in the ongoing conversations and contributing to the future of open-source software in the months ahead, until we meet again at FOSDEM 2026!