Taking on new engagements
Freelance data and AI engineer · Copenhagen
Data platforms that hold up. AI coding that actually ships.
I’m Mathias. At two companies I’ve had technical responsibility for the whole data platform, from raw data to the reports the business runs on. Companies bring me in to build or fix theirs, or to get real output from AI-assisted development. Often both.
ResultsFrom recent client work on a platform handling more than 60 million records.
See the cases72% from 25%
A ranking model found 72% of the valuable cases using a quarter of the processing budget. The old selection found 25%.
Tested on two months of historical data
−98.5%
A nightly job rewrote 46 million rows to change 683,000. Now it touches only what changed.
Measured in production
2–4.5×
Duplicate workload traced to a single fault that had gone unnoticed because nothing looked broken.
Measured in production
Two things I’m hired for
Data platform expertise
Pipelines, warehouse, data models, reporting and the machine learning on top: designed, built, or untangled. For companies whose data has outgrown its setup, or never had a proper one.
- New platforms built from scratch
- Slow, costly or fragile platforms fixed
- A senior engineer embedded in your team
AI coding expertise
AI coding agents set up properly in your codebase, with the conventions, guardrails and connections that turn a demo into daily output, and a team that knows how to use them.
- Agent setup in your repositories
- Guardrails, permissions and review flow
- Hands-on training for your developers
How to hire me
Buy hours, or buy a result.
Hours
A senior engineer in your team, part-time or full-time, for as long as you need. The most common way companies work with me.
- Hourly rate, agreed up front
- Start small and scale up
- No lock-in: stop when the work is done
Fixed scope, fixed price
Data platform review
I go through your platform and tell you what it costs, where it is fragile, and what to fix first. You get a written, prioritised report and a walkthrough.
5–8 days of work, over 2–3 weeks
Ask for a quoteFixed scope, fixed price
AI coding setup
Coding agents set up in one team or codebase: conventions, guardrails, connections to your systems, and hands-on training so your developers keep using it.
6–10 days of work, over 3–4 weeks
Ask for a quoteWhy me
Both halves of the job.
I’ve owned the whole platform
Technical responsibility for the data platform at two companies: architecture, pipelines, warehouse and reporting. Not one corner of it.
I build it myself
Hands-on, not a slide deck. I have built every layer: pipelines, warehouse, machine learning models, reports and forecasts.
I measure before and after
A baseline first, so the effect of the work can be shown rather than claimed.
I can explain it
To developers in their terms and to management in theirs. Forecasts I built have gone into company budgets, and I have been a manager myself.
AI coding is how I work
I do most of my own engineering with coding agents, and I have restructured a production data platform so agents can work in it.
I build to hand over
Conventional, documented, and owned by your team when I leave.
“Mathias must be one of the most intelligent Data Engineers I’ve ever had the pleasure to work with. He has a remarkable talent for drilling down the most complex data projects into understandable and actionable insights and maintains a focus on problem-solving at all times.”Before you write
- What does it cost?
- Hours are billed at an hourly rate, products at a fixed price. Both are agreed before any work starts. You get a number after a short first call.
- How soon can you start?
- It depends on what I have running. Ask, and I’ll tell you my current availability straight away.
- Where do you work?
- On-site in Copenhagen, remotely everywhere else. In English or Danish.
- How is it contracted?
- Through my company, MLN Data Consulting (CVR 45700577). Your standard consultancy contract and NDA are fine.
- What if you’re not the right fit?
- Then I say so on the first call, before it has cost you anything.
Tell me what you need.
Three lines is enough. I reply within one working day with how I’d approach it and what it would take.
- No cost and no obligation
- A straight answer on whether I can help
- A price before any work starts