S. Ostermann

Stefan Ostermann Independent software consultant

Software at a fixed price and AI that never leaves your building.

For mid-sized companies that need predictable costs and will not hand their data to someone else.

Twenty years of experience with software that scales help with that. Most recently as Head of Development, now independent in Hamburg.

Stefan Ostermann

01 — About

After many years leading software and product development, most recently as Head of Development, I am going independent in October. What used to need a team can now be done alone, because agents handle the grunt work in the background.

I use established technology and new methods: custom software at a fixed price, built on proven design patterns and with AI assistance. Compliance with standards and regulations such as GDPR and ISO 27001. AI, private or public, depending on the use case and what it suits.

My measure: fewer slides, more results. The time that used to go into meetings and coding by hand now goes into specification and into working with people.

02 — Availability

Projects start in October, conversations and scoping right away. I am available for projects, sparring and partnerships.

I am starting solo, with a clear plan to grow together with a partner.

03 — What I offer

Custom Software

I build software end-to-end: analysis, development, operation. AI-assisted, so it moves fast. Your code and data stay 100% in-house. At a fixed price, not on a daily rate.

Private & Local AI

Open models like Gemma or Qwen on your own hardware. Contracts, customer data and source code stay inside the company. From choosing the hardware to day-to-day operation.

How a private AI project runs →

eCommerce & Scalable Systems

Platforms handling up to 100,000 orders a day and product catalogues of more than a million SKUs, mostly fashion and mixed assortments. Sixteen years in that environment: architecture, peak load, and the release discipline that keeps a shop fast while it grows. I run projects like these and choose the systems they run on.

Interim Engineering Leadership

I run your development team from the inside: planning, releases, budget. And I make sure the business side and the engineering side speak the same language. For a growth phase, a gap after a departure, or a project that has outgrown its structure.

Information Security & Compliance

I have worked hands-on through ISO 27001 and TISAX certifications and built GDPR-compliant systems. I have guided pen tests and I train developers on the OWASP Top 10. I will take you through a certification process. For German Mittelstand companies that have to take security and data protection seriously.

04 — Experience

since October 2026
Independent Software Consultant
Stefan Ostermann, Hamburg
2025 — 2026
Head of Development
eos.uptrade (Siemens Mobility), Hamburg
2018 — 2025
Director Product Development novomind iSHOP
novomind AG, Hamburg
2015 — 2017
Project & Partner Management novomind iSHOP
novomind AG, Hamburg
2009 — 2015
Project Lead novomind iSHOP
novomind AG, Hamburg
2005 — 2009
Software Developer
Various Companies
2005
Diplom-Informatiker (FH), Computer Engineering
Osnabrück University of Applied Sciences

07 — Network