Why Data XL
Data XL was founded by engineers Fitti Weissglas and Petra Schäfer, who have spent years working closely with data — building systems, fixing broken ones, and living with the consequences when they were designed poorly.
Much of what we know was learned the hard way. We have seen how data projects fail quietly: through unclear definitions, fragile pipelines, tools chosen too early, systems built without understanding how data is actually produced and used — or simply because they produced the wrong numbers. We have also learned how not to do it.
Working across public health, epidemiology, and large operational programmes taught us that data is a discipline of its own. It requires care, structure, and proper systems around it. Without that, even the best intentions collapse into spreadsheets, workarounds, and mistrust.
Data XL exists because we wanted to do this work properly.
Not improvised. Not trendier. Properly.
Serious about technology
We care deeply about how systems are built. Doing data work properly means choosing technology deliberately, designing for failure, and taking security and operations seriously from the start.
We take pride in using solid, well-understood technology stacks, securing data across environments, and building systems that can be operated, monitored, and maintained over time. Not because it is fashionable, but because this is what responsible data work requires.
Based in East Africa
We are based in East Africa, with our core team in Nairobi and team members in Kampala. From there, we work with organisations that handle complex and sensitive data — in Africa and in Europe, starting in the Netherlands.
Today, Data XL continues the work we are good at: designing and operating data systems that respect the data, the people behind it, and the decisions it informs.
Contact us
You can reach us at .