Christian Zielinski, PhD · Head of IT Infrastructure in public healthcare

Making complex IT landscapes steerable.

Enterprise architecture, IT governance, and secure IT operations. I reduce complexity in architectures, responsibilities, and operations.

A decade of architecture and technology leadership across insurance, energy, and finance.

01 · Profile

About

I am a technology leader focused on making complex IT environments steerable: through clear target states, working governance, and secure, reliable operations.

As Head of IT Infrastructure at a public-law body in the German healthcare system, I lead a department of 20 people at strategic and operational level, working through two team leads. My mandate covers infrastructure strategy, division-wide IT security in close collaboration with the information security office, Microsoft 365, service quality and governance, the orderly transition of new technologies into regular operations, and practical AI enablement in IT operations. The organization secures ambulatory medical care for 9.5 million people.

Before that, I led technical architecture for a major European insurance group within its shared group IT organization: heading an internationally distributed architecture team, co-establishing architecture standards across the insurance group and its reinsurance parent, operating architecture governance across portfolios, and steering modernization and simplification initiatives. Earlier roles at an international energy company and a consultancy focused on the financial industry centered on platform modernization and large-scale data and analytics architectures in regulated industries, including cloud and hybrid platforms.

I started out as a computational physicist (PhD, NTU Singapore, ten publications), which still shapes how I work: analytical, structured, careful about complexity and trade-offs. What interests me most is where strategy becomes execution: operating models, decision structures, and ownership teams can actually work with.

How I lead

I lead by designing the system: clear ownership, decision paths that come with reasons, and target states people can navigate by. Decisions are made once, documented, and then relied on; commitments are kept or renegotiated early, never dropped silently. Change comes in staged, controlled moves, sized to what the organization can absorb. Structure is for systems; with people I adapt: delegation follows maturity, and conflicts get mediated rather than decreed. When the structure is right, reliability stops being a struggle and becomes a property of the system.

Background

Before industry I spent a decade in physics: studies in Heidelberg, PhD in computational physics at NTU Singapore, a research stay at the University of Wuppertal, ten publications in lattice field theory and high-performance computing. Physics did not teach me technologies. It taught me how to take a complex system apart, model it honestly, and respect what the data says.

Hands-on

My foundation is technical: years of hands-on architecture and engineering work, and a working view of the stack from identity and networking to data platforms. A selection of side projects is on GitHub, including portfolioopt, a portfolio optimization library with over 300 stars.

Personal

I live in Düsseldorf and spent several years in Singapore during my PhD. Outside work I enjoy 3D printing, turning ideas into something you can hold.

02 · Focus areas

What I work on

Technology leadership and operating models

Structures, roles, and decision paths that make an IT organization effective.

Enterprise and technical architecture

Target states, standards, and reference architectures that hold up in practice.

IT governance

Governance as decision enablement: fewer gray areas, traceable decisions.

Infrastructure strategy and secure operations

Reliability, Zero Trust, security-by-design, service quality.

Modernization and build-to-run

Reducing landscape complexity and technical debt, orderly transitions into regular operations.

AI in IT operations

Practical enablement for automation, knowledge access, and operational relief.

03 · Writing

Notes

Occasional notes on technology leadership: governance, operating models, infrastructure, and AI in IT operations. New notes appear here first.

04 · Technology

Hands-on

A hands-on foundation, not a developer portfolio. A few projects I keep public:

Python · 300+ stars

portfolioopt

Financial portfolio optimization in Python: Markowitz, minimum-variance and tangency portfolios. A compact example of programming, mathematics and practical problem solving meeting in one place.

View on GitHub
Talk · Cryptography

Secure multi-party computations

A technical talk on cryptographic protocols and distributed trust: mathematically grounded computer science with a clear connection to real systems.

View the talk
Python · Analysis

hanzifreq

A frequency analysis of Chinese characters: the kind of small, well-defined side question I find hard to leave alone.

View on GitHub
05 · Research

Academic background

Before industry I worked in computational physics: lattice field theory, large-scale numerical simulations, high-performance computing. Ten publications, including in Physical Review D; the full list is on arXiv and ORCID. That background is why I treat IT landscapes as systems: quantify, simplify, verify.

Thesis · 2017

Theoretical and computational aspects of new lattice fermion formulations

PhD thesis, Nanyang Technological University: lattice fermion formulations, numerical methods, and the theory behind them.

Read on arXiv
Paper · Phys. Rev. D · 2016

Spectral properties and chiral symmetry violations of (staggered) domain wall fermions in the Schwinger model

Lattice fermions and chiral symmetry, studied in a controlled setting.

Read on arXiv
Paper · Phys. Rev. D · 2013

Thirring model at finite density in 0+1 dimensions with stochastic quantization

Stochastic quantization and finite-density problems, checked against an exact solution.

Read on arXiv
06 · Contact

Get in touch

The most reliable way to reach me is LinkedIn. For code and notes, GitHub; for the physics record, arXiv.