200 people, two stages, one common goal: on 21 May 2026, the Sovereign Cloud Stack (SCS) community came together at bUm Berlin - and this year's SCS Summit made it clearer than ever that digital sovereignty is no longer a vision of the future, but an everyday reality. The main programme with panels, keynotes and political impulses took place in the auditorium; at the same time, the bUm Box filled the entire day with technically in-depth practical presentations. The energy in the room was palpable: this community is really making a difference.
A historic moment as a starting signal
Anja Voß (DigitalHub.SH) and Lisa Seifert (Forum SCS-Standards) kicked off the day together, followed by the speakers of the Forum SCS-Standards Ralph Dehner (B1 Systems), Janis Kemper (Syself) and Felix Kronlage-Dammers (Head of Forum SCS-Standards), who focussed on an important milestone: In March 2026, the IT Planning Council made the SCS standards mandatory in the German stack. What was long considered an ambitious goal has now become a political reality. Dr Matthias Burgfried from the Federal Ministry for Digital and State Modernisation (BMDS) then gave an update on the status of the German stack: where do we stand, what challenges remain and what are the next steps?
The IT Planning Council's decision was a recurring theme throughout the entire day - it is not only a recognition of the work of the community, but also a clear mandate: the infrastructure must now scale, the standards must be applied across the board.
Why so many standards?
The first major panel of the day, moderated by Miriam Seyffarth (OSBA), posed precisely this question: „Why so many standards? Digital sovereignty between SCS, C3A & Co.“ Luise Kranich (BSI), Dr Kai Martius (secunet), Joachim Astel (noris network) and Dr Lea Beiermann (ZenDiS) took to the stage - a panel that could hardly be more different and was therefore productive. The answer that emerged was that standards only create real added value if they interlock and if the benefits for users are clear. The SCS is not a competing product to other initiatives, but a building block in a larger ecosystem.
The second panel of the day - „Open source standards in practice“, moderated by Dr Daniel Gerber (ALASCA) - shed light on the perspective of those who implement the standards on a daily basis: Cloud&Heat, OSISM and UhuruTec spoke openly about how they work together as direct competitors in the same SCS forum, what this means in practice - and what consequences the IT Planning Council decision has for their customers and products.
Prof Dr Karin Vosseberg from Bremerhaven University of Applied Sciences provided a different perspective: she presented how digital sovereignty, open source and sustainability are actively integrated into computer science teaching as a triad. A reminder that digital sovereignty is not just an infrastructure issue, but also an educational issue - and that the next generation of developers will decide how sovereign our digital future will be.
From theory to production
One of many practical insights came from Martin Seebe (DATEV) and Matthias Haag (UhuruTec): Since 2025, DATEV, the largest IT service provider for tax consultants, auditors and lawyers in Germany, has been operating an SCS-compliant IaaS platform in production - built on YAOOK and uStack, fully managed with GitOps. This is no longer a pilot project. The fact that a company of this size and with this level of responsibility is relying on SCS-compliant open source infrastructure is a strong signal for the entire community.
At the same time, Michel Raabe (B1 Systems) and Daniel Pfanz from Körber Pharma demonstrated in the bUm Box what a migration from Red Hat OpenStack to an OSISM-based environment means in practice: network redesign, data transfer of running workloads, architectural differences - and in the end the realisation that the effort is worth it, because full control over your own infrastructure is not a matter of course.
Sovereign AI and the next stack
One topic that attracted a lot of attention this year was AI - and the question of whether digital sovereignty is also possible in the age of AI. Christoph Streit (ScaleUp Technologies) showed the audience how SCS infrastructure can serve as the basis for the provider-independent operation of language models and other AI applications. It was not just about infrastructure, but also about fundamental questions: What is really behind the term „open source AI“? Streit shed light on the so-called „openness spectrum“ and analysed where providers use the „open“ label without offering genuine openness - keyword openwashing. Genuine technological independence, he concluded, does not need compromises - it needs the right open standards and a critical understanding of what „open“ really means.
The talk by Cloud&Heat and Cloudogu in the bUm Box pointed in the same direction: Sarah Günther and Johannes Schnatterer jointly presented what a complete open source stack could look like - from the SCS-certified OpenStack infrastructure to an operating platform for tool stacks through to the end users. Freedom of choice not only at infrastructure level, but also in the software tools used by users - exactly what the German stack demands.
Kubernetes, storage and community depth in the bUm Box
Those who switched to the bUm Box in the afternoon dived deep into the technical realities of the SCS ecosystem. Chris Werner Rau (teuto.net) presented an open-source cluster API control plane provider for sovereign Kubernetes - without proprietary dependencies, fully declarative and GitOps-friendly. Janis Kemper (Syself) gave insights into two and a half years of operating a Kubernetes-as-a-Service platform based on the SCS Cluster Stack Framework: What works, what is complex, and how do you reliably operate databases in Kubernetes?
The Kube3 project showed that digital sovereignty is also arriving in the higher education sector: Bavaria, Baden-Württemberg and North Rhine-Westphalia are jointly building federated KaaS systems for universities - by universities. Lena Becker (RWTH Aachen) and Martin Mai (University of Bamberg) emphasised the special requirements and challenges of this sector - and that the SCS serves as a concrete orientation framework.
Joachim Kraftmayer and Mario Listes from CLYSO concluded the bUm Box with a look behind the scenes of open source development: What does it mean to be a maintainer of Ceph and Rook - two of the central storage projects in the cloud-native ecosystem? A question that is rarely asked so directly and that shows the responsibility behind active community involvement.
Certificates, quizzes and a long evening
The Certificate Award Ceremony was the emotional finale in the auditorium: five companies were presented with their SCS certificates. artcodix and dNation were honoured as „Certified SCS IaaS Integrator“. Cloud&Heat Technologies received the „Certified SCS-compatible IaaS“ certification. A particular highlight was the awarding of the „Certified SCS-compatible KaaS“ certification to Syself and noris network - it confirms the conformity of their Kubernetes-as-a-Service offerings with the SCS standards and emphasises the growing importance of open, compatible cloud solutions. Each of these certifications is a clear commitment to interoperability and digital sovereignty - and shows that the SCS ecosystem is being put into practice and is growing. Before that, there was an SCS quiz show - with questions about the history, goals and the trials and tribulations of the initiative, which produced many a smile, but also some surprising insights.
The community rounded off the day at the evening get-together on the Landwehr Canal - new contacts, old connections, initial ideas for the next joint project. This is exactly what the SCS Summit is made for.
See you next year
The SCS Summit 2026 showed how far the community has come in a short space of time: Standards that work. Infrastructures that are in production. Political tailwind that is stronger than ever before. And a community that is not just discussing, but building.
Save the date: The next Sovereign Cloud Stack Summit will take place on 22 April 2027.
We look forward to seeing you!
