Fractional CTO · Utrecht, NL
I help growing tech-driven companies scale their engineering, modernise their platform, and turn AI into reliable production systems.
Hands-on fractional CTO leadership for companies where technology carries the business — whether you sell software or ship a physical product. I stay in the architecture and the code, not just the slides, usually for three to nine months.
- 15+ years
- Media · Finance · E-commerce · Agritech
- AWS · Azure · GCP
The situation
You’ve outgrown the way you build software.
The business is growing. The technology that got you here — and the team behind it — is starting to creak.
- Releases have become slow and unpredictable.
- The architecture that was right at ten people is fighting you at thirty.
- AI initiatives are stuck between a promising demo and production.
- Cloud spend is climbing faster than revenue.
- Critical knowledge lives in one developer’s head — or at an external agency.
- Your data sits in GA4, spreadsheets, and vendor dashboards — everywhere except where decisions are made.
- A founder is still effectively acting as CTO — or nobody is, and the board feels it.
You need senior technical leadership, but not yet a permanent CTO. That’s the gap I step into.
What I do
Three problems I’m hired to solve.
- 01Scale your engineering organisationTurn a team that ships by heroics into one that ships predictably — process, architecture, hiring, and delivery quality.
- 02Turn AI into production softwareGet past the demo. Real LLM and data systems that run reliably, are evaluated honestly, and earn their place in production.
- 03Modernise your platformMigrate, stabilise, and right-size — cloud architecture, observability, reliability, and cost under control.
Selected work
A few engagements.
Anonymised, but the numbers are real. Named references available on request.
Fractional CTO — multi-tenant agritech SaaS
Owned technical strategy and the scaling roadmap for a multi-tenant quality-inspection platform, reported to the board, and grounded the roadmap in an analysis of 3,500 delivery tickets. Shipped offline-first quality checks so inspectors keep working inside shipping containers and cold stores when the network drops.
25–50% of Azure spend identified as recoverable
AI/ML platform engineer — international e-commerce group
Built a cloud-native data platform on AWS streaming first-party and analytics data from 13+ webshops in eight countries into an in-house ClickHouse lakehouse, plus an MCP server letting non-technical staff query live business data through Claude. A custom Kubernetes operator provisioned whole data feeds from a single manifest, on a few hundred dollars of infrastructure a month — handed over to a managed vendor at the end.
New-feed onboarding: weeks → minutes
Co-founder & CTO — ML personalisation
Took an AI personalisation product from zero to market fit and ran engineering as it scaled, serving real-time recommendations to millions of users for major Dutch broadcasters — under contractual SLAs, with continuous A/B testing in production.
20%+ lift in pageviews across major clients
Lead data platform engineer — asset management
Led a cross-functional team of around ten — engineers, analysts, and modellers — building a cloud-native, ML-ready data platform for financial risk and forecasting, running sprint planning and hiring.
Cross-functional team of ~10
Also: a next-generation media analytics platform processing 50+ TB per day, and Flywheel — an open-source GitOps dev-loop tool I built and use on engagements.
How I work
Senior leadership that still ships.
- / 01
Hands-on, not hands-off.
I lead from inside the work — architecture, code review, and the hard implementation — alongside strategy and the board conversation.
- / 02
A fixed window, a clear mandate.
Engagements usually run three to nine months with explicit goals, so the value is obvious and the exit is planned from day one.
- / 03
I leave you stronger, not dependent.
The aim is a team and a platform that no longer need me: standards, documentation, and people who can carry it forward. My last platform build ended exactly that way — a documented handover to a managed-services vendor.
- / 04
Strategy you can act on.
Architecture reviews, roadmaps, and cost and risk reporting that a board understands and an engineering team can execute.
Where to start
Most engagements start with a two-week review.
Two weeks inside your architecture, your cloud bill, and your delivery process. You get a written review, a board-ready presentation, and a prioritised 90-day plan — whether or not we work together afterwards.
€9,500 · fixed price
About the review
Who you’d work with
Matthijs van der Kroon
I’ve spent 15+ years building production data and AI systems — as a co-founder and CTO, as a platform architect, and as the engineer in the room. I’ve led teams, reported to boards, and shipped systems processing tens of terabytes a day across media, finance, e-commerce, and agritech. MSc in Software Engineering, cum laude. Based in Utrecht.
More about meNext step
Let’s talk about where your engineering is heading.
A 30-minute call, no pitch. Tell me what’s slowing you down and I’ll tell you honestly whether I can help.
Prefer a bounded first step? Start with the two-week review