STACKIT delivers secure EU-based cloud services with MongoDB

Intro

When Schwarz Group, the multi-national retailer behind brands Lidl and Kaufland, struggled to find a cloud service that offered the data sovereignty and autonomy it wanted, it responded by building its own. To ensure that the Group is future-ready—and to stay ahead of the competition—it required a dynamic, flexible and independent cloud infrastructure.

So in 2018, the company launched STACKIT, a cloud platform providing scalable and secure services to the Group’s subsidiaries. It would be part of Schwarz IT—the IT service provider for the whole Schwarz Group, providing everything from data center capacity, operating system hardware, backup solutions and databases, to SAP systems and operations in the cloud.

Supporting complexity and accessibility to meet business needs

Schwarz Group’s absolute commitment to data sovereignty influenced every part of creating the STACKIT cloud platform and the portfolio of managed services offered around it. “For us, it's crucial to know who has access to our data,” says Richard Siekmann, Domain Product Owner at STACKIT. “We want to ensure that only we are able operate it and know who’s accessing it.”

Central to achieving that was having a database that could not only handle an enormous volume of often-complex data structures, and which could also function without requiring data to reside on external third-party servers or dedicated hardware. Schwarz Group found MongoDB to be the best option to meet its needs.

The cross-platform, document-oriented database management system has significantly simplified how the retail group stores and manages data. It allows STACKIT to structure information in complex hierarchies while keeping it instantly accessible for fast queries and indexing. Meanwhile, its popularity among developers is assured.

“Our developers love MongoDB because they never have any trouble with it. It’s so easy, I'm pretty sure I could teach it to my eight-year-old son,” says Siekmann. “Everything is flexible inside of MongoDB. We benefit from the performance and scalability of the cloud while also managing our costs, and most importantly we always have complete control of our data.”

Realizing a new value proposition

STACKIT’s success quickly revealed a unique market opportunity for Schwarz Group: a high-performing, cost-efficient cloud alternative that ensures EU data residency. With data sovereignty becoming increasingly critical—especially for regulated industries—offering STACKIT’s services to external customers made obvious commercial sense. “Clearly we are not alone in the desire (for data sovereignty) and European data laws are quite different to elsewhere,” says Seikmann.

In September 2024, STACKIT was spun out as an independent company offering enterprises—particularly those in highly regulated industries—a cloud solution with genuine data sovereignty. Siekmann points out that Schwarz IT was already used to working at scale for a huge number of internal customers (4,000 people managing infrastructure and software for 550,000 users). “We have more than 23,000 servers across data centers in Germany and Austria, 30 petabytes of data, 1.4 million network ports, and one of the largest SAP retail systems in the world,” he explains.

The most important lesson? “Have a clear and respectful discussion about what you can deliver and commit to making it happen in a clear timeframe,” says Siekmann. “If you don’t listen and if you don't commit yourself, you can’t meet expectations.”

And meet expectations they did. STACKIT now offers external partners and customers alike adaptable, high-performance solutions for a wide range of needs—whether it's traditional infrastructure outsourcing, modern development environments, first-time cloud adoption, or scaling existing workloads. Not only that, but the success the company enjoyed inside Schwarz IT, is translating to the outside world. “At the beginning, everyone was laughing at us, a retailer trying to offer IT services,” says Seikmann. “But we’re growing quickly and now the market and other hyperscalers are taking us much more seriously.”

Ensuring reliability and performance

STACKIT organizes its database offerings into two categories: partner-managed databases and in-house developed solutions with the latter all running on Kubernetes within STACKIT’s OpenStack-based infrastructure. Partner databases such as MariaDB complement this portfolio, giving customers the flexibility to choose what best fits their needs. MongoDB supports several critical workloads, including—notably—the automated food ordering system for Lidl stores.

Every night, STACKIT calculates stock requirements— “two or three thousand units”—for each of Lidl’s 11,500 stores based on individual store hours and inventory. These parallel calculations feed directly into logistics execution, showcasing the platform’s scalability and operational impact. “We have a very limited time where my colleagues are able to calculate the data, so they need to have a reliable and performant environment,” says Seikmann. “And this is what we are providing them with MongoDB.”

“They’ve never had any trouble with it, and I’ve never had any negative feedback—which means I can sleep at night!” he adds.

Conclusion

In outlining plans for STACKIT, which recently signed Bayern München as a customer, Siekmann presents a soccer analogy. “Right now, we are playing good football, giving our fans what they want, but in the next couple of years we will come to the Champions League with even greater demands from our customers.

“They want a lot of technologies and features that are well known from the hyperscalers, while maintaining data sovereignty. Building things like that is challenging, but that’s what you do if you want to play in the big league. Big companies in Germany are already using STACKIT and we are just growing, growing, growing.”