Czech Republic · Available for work
Network Architect & Ethical Hacker. I design networks that hold under pressure — and then I try to break them.
Network architect and ethical hacker working across healthcare, public administration and large-scale enterprise contracts. I build the infrastructure, harden it, and validate it from the attacker side.
Three disciplines that reinforce each other: I design the network, I build the detection that watches it, and I attack it to find out where the design was wrong.
Design and delivery of enterprise networks — from campus and datacenter topologies to segmentation strategy and next-gen firewall policy.
Building the monitoring layer that actually catches things — SIEM pipelines, log coverage, alerting that operators trust rather than mute.
Offensive validation of infrastructure and applications, with reporting written for the people who have to fix it.
Helping teams move faster on new technology without trading away resilience or security posture.
Products that came out of real operational problems, plus work outside the infrastructure world.
A network configuration system built around the problems I kept hitting in the field: configuration drift, undocumented changes and no reliable rollback path. NetVault NCS keeps device state versioned, auditable and recoverable — with scheduled backups, drift detection, assessments and a built-in network assistant.
Proxy and edge infrastructure management built for environments where every egress path has to be accounted for. Auditable configuration, high-availability design and SSO-backed access, from the perspective of someone who has had to defend and attack the same perimeter.
A complete web platform delivered end to end — design, build, deployment and ongoing operation behind a hardened reverse proxy. Multilingual (EN/AL/CZ), with service ordering and two distinct business lines under one site.
A side project outside the infrastructure world — a mobile application designed to help people improve and maintain their relationships. Currently in active development.
Every layer of the stack I design today is one I used to support by hand. That path is the reason the designs hold up in operations.
Where it began. Learning how systems actually break for the people using them, and how to explain a fix in plain language.
Broader responsibility across infrastructure — servers, endpoints and the first real exposure to network design decisions.
Moving into dedicated networking: routing, switching, firewalls and the operational discipline that regulated environments demand.
Designing network architecture for healthcare, public administration and large-scale contracts — while running blue team detection engineering and offensive testing on the other side of the same systems.
Network architecture and security testing in environments where availability is a patient-safety concern.
Infrastructure delivery and offensive validation under public-sector compliance requirements.
Architecture and delivery on enterprise projects with long horizons and many stakeholders.
I came up through helpdesk, IT support and network engineering before moving into architecture. That route matters: I have been the person paged at night for the design decisions someone else made, so I design with that person in mind.
On the defensive side I build detection that operators keep switched on — Wazuh, SIEM pipelines, Zabbix. On the offensive side I run penetration tests and red team engagements, mostly in healthcare and public administration, where the stakes of getting it wrong are not theoretical.
New technology is the part of this job I have never gotten tired of. AI is the current wave, but the interest is broader than that: I want to keep pushing myself forward, and the organisations I work with along with me.
Whether it is architecture for a new environment, a detection stack that needs to actually work, or an honest penetration test — send me a mail and tell me what you are dealing with.
Jan1996@email.cz