Stephan Preeker

Stephan Preeker

Data and software engineer. Building open tools for nature, climate, and public data. Founder of datalegends.nl.

I work on open-source software for the public sector. Public money, public code.

Track Record

• python-snap7 — Co-created the open-source PLC communication library. Around 50 million downloads for a niche industrial automation problem.
• DEGO & DOOK — Built data platforms for energy transition and public safety, used by Dutch municipalities.
• Signalen.org — Core contributor to the open-source issue reporting system used by municipalities across the Netherlands.
• Amsterdam Data — Built the municipal data platform at data.amsterdam.nl.

Current Work

• Nature data — Working on biodiversity and habitat data infrastructure in the Netherlands. The current systems need improvement; I'm building better ones.
• AI-powered engineering — Moving from traditional data engineering to agentic, AI-assisted tooling.
• datalegends.nl — Data stories and experiments.

Find Me

• Code: gitlab.com/spreeker
• Stories: datalegends.nl
• Email: stephan@datalegends.nl
• Code for NL Fellow: codefor.nl/code-fellows