jreisinger.github.io

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I’ve been securing, operating and building computer systems for about 15 years. This includes writing programs. I started out as an IT auditor and system administrator, later moved to DevOps and security engineering. I’ve also managed projects and teams.

Employment history

Sr. Security Engineer at Empatica [2022 - present]

Setting up security monitoring.

Sr. Security Engineer, Team Lead at Deutsche Telekom Pan-Net [2017 - 2022]

Built security products (WAF, SIEM).
Developed programs and scripts using Go, Bash and Python.
Maintained Ansible playbooks, Kubernetes manifests and CI/CD pipelines.
Operated systems in private (and public) cloud the DevOps way.
Managed projects and team.

Security Engineer at First Data [2016 - 2017]

Did full-stack administration of a large log management solution based on Splunk, syslog-ng, Linux.
Implemented a monitoring system using Python, Perl and Bash.
Implemented a testing environment using VirtualBox, Vagrant, Ansible.

Sr. Linux Systems Specialist at Eset [2015 - 2016]

Administered Linux (Debian/Ubuntu) servers and services running on top of them (e.g. MySQL, Postfix).
Introduced a configuration management tool (Ansible) and some other DevOps patterns like infrastructure as code, automated testing.

System and Network Administrator at Institute of Science and Technology Austria [2013 - 2015]

Took care of Linux based infrastructure (email system, web servers, file servers, DNS) and networking.
Built tools and automated tasks via Perl, Bash and Ansible.
Wrote software for monitoring backups and virtual machines using MySQL and Perl Dancer.
Started to migrate monitoring system from Nagios to clustered Icinga2 setup.

System Administrator at Kedros [2009 - 2011]

Administered internal Linux (Debian) based infrastructure.
Setup and maintained testing environments (Solaris, RHEL, Tomcat, Oracle) in collaboration with developers and testers.
Wrote automation scripts in Unix shell and Perl.
Managed projects’ deliverables.

IT Auditor at Slovak Telekom [2004 - 2006, 2011 - 2013]

Performed audits in IT, networking and IT security areas (e.g. Internet facing applications security, PKI review, Security of remote access, Patch management and vulnerability assessment).
Administered internal lab consisting of Linux servers and Cisco networking devices.
Managed small (up to 4 people) audit teams.

Current main technologies

Platform: AWS

Operating system: Kubernetes, Linux

Artificial languages: Golang, Bash

Natural languages: English, Italian, Slovak

Certifications

CKA: Certified Kubernetes Administrator [2022 - 2025]

CKAD: Certified Kubernetes Application Developer [2021 - 2024]

CCENT: Cisco Certified Entry Networking Technician [2013 - 2016]

LPIC-2: Linux Professional Institute Certification - Advanced Level Administration [2012 - 2017]

CISSP: Certified Information Systems Security Professional [2011 - 2014]

CCNA: Cisco Certified Network Associate [2006 - 2009]

Formal education

Cisco Networking Academy: networking and telecommunications, four semesters [2005 - 2006]

University of Florence: economics and IT, one semester [2003]

University of Economics in Bratislava [1998 - 2004]

Bilingual (Slovak - Italian) high school [1993 - 1998]