Stephanie Jonkers
BerlinEngineerFounder-in-progress

I build thoughtful systems and write about what I learn.

I’m an engineer and founder-in-progress based in Berlin, working on trustworthy AI systems, agentic workflows, and the questions about structure and uncertainty that keep pulling me back to physics.

Read my latest essay View CV
02 — About

Systems, people, uncertainty.

I have a background in electrical engineering and machine learning, and have worked across data science, product, and engineering leadership.

Much of my work has focused on reliable systems in regulated environments, where correctness, evaluation, and trust matter as much as innovation.

Recently I’ve been drawn toward founding, building with coding agents, and thinking more carefully about what makes a specification useful for both humans and machines.

Somehow, I keep returning to physics, astrophysics, and quantum mechanics because they sharpen how I think about structure, uncertainty, and what is actually knowable.

03 — What I’m building now

Agentic Blue

Addressing agentic workflow reliability and quality assurance through risk consideration, targeted evaluation, and trace analysis.

Website coming soon
Live pre-release alpha · v0.6.0-alpha

Reliability intelligence

Connect production traces and failed eval runs to evidence-backed findings, targeted validation, and proof that fixes worked.

Try the alpha ↗
Live pre-release alpha · Team project

Automatic Risk Evaluation

Define your system’s application scope. Automatically generate meaningful risks, scenarios, and evaluation test I/O—and keep your eval set meaningful.

Try the alpha ↗
05 — Work and perspective

Built across disciplines.

The through-line is not a particular technology. It is making complex systems more understandable, dependable, and useful.

01
Now

What I'm building

I’m exploring the path of becoming a technical founder: building with coding agents, thinking carefully about agentic workflows, and designing specifications that help humans and machines do better work.

02
Selected work

Engineering and product

I’ve worked across machine learning, data science, product, and engineering leadership, often in regulated environments where reliability, explainability, and trust matter as much as speed.

03
Writing

Ideas and reflections

I write about my experiences building with coding agents, automating workflows with agents, helping others understand their application behaviour and everything in between!

04
Perspective

What I care about

Thoughtful technology, sustainable ambition, elegant engineering, the physics of our reality, and building companies and tools that people can actually trust.

06 — More

Things I’m exploring.

01

Founder notes

Notes from shifting from engineering depth toward founder-shaped thinking.

02

Books that shaped my thinking

Reading that changed how I think about systems, boundaries, focus, and the world.

03

Engineering principles

When we have built an excavator, we no longer need to dig with spades.

04

Lessons from burnout

Motivation is not enough. The other things I wish I had understood sooner.

05

Projects just for fun

Small code projects, why I built them, and a few things I learned along the way.

06

Physics, systems, uncertainty

Sometimes the real question is the one that brings us closer to the truth.