Microsoft Windows Experts in Stuttgart

• Analysis of the existing CAN communication between microcontrollers
• Analysis of the sensors used and the measured values collected
• Planning the CAN messages for transmitting the measured values
• Iterative adjustment of the microcontroller code to the new CAN messages
• Cross-compilation from x64 to arm64

• Development and introduction of operations processes
• Preparation of complete documentation packages (including incident management and operations support) to meet compliance requirements
• Introduction of a workshop on IaC (Infrastructure as Code)
• Technical consulting for the project security concept (ISMS)
• Installation and operation of Kubernetes clusters on AWS, on-prem, and Azure
• Hybrid cloud architecture design (on-prem, Hetzner, AWS)
• Analysis and troubleshooting of incidents and system outages
• Network adjustments for firewall rules, gateways, OpenVPN settings, and IPsec tunnels (pfSense)
• Technical consulting on Bitbucket, Jenkins, and GitLab CI/CD pipelines
• Consulting on Ansible deployments and infrastructure automation
• Consulting on building a scalable system in the cloud (AWS / Azure)
• Technologies / Tools: Ansible, Terraform, AWS, Azure, VPN, pfSense, Jenkins, Bitbucket, Kubernetes, GitLab Runner, ISMS, Golang, Prometheus, Grafana, S3, Lambda, RDS, ECS, Cognito, OIDC, Harbor, MinIO, Postgres, Redis, Keycloak, Ceph, Proxmox, CloudFormation, PostgreSQL, Flux CD, Hetzner, IONOS, Sonatype Nexus Repository, Entra ID, Dex IdP, Pulumi

• Developing the infrastructure and improving existing infrastructure: Jenkins, Gitlab Pipeline, OpenShift, Docker, Helm Chart, Kubernetes, Artifactory, CodePipeline, CodeArtifact, Python
• Documenting solutions in Jira/Confluence
• Supporting other colleagues in different technical areas

• Development of a new generation of Spring Boot microservices for an archiving system on OpenShift, monitoring, security analyses

Stack: Java, Spring Boot, Kafka, Vaadin, OpenShift 4.x, Maven, Artifactory, Jenkins, Git/Github, GitHub Copilot, GitOps, CI/CD, Kargo/ArgoCD

• Develop hardware drivers and middleware using C++11, Java and Python
• Design of various RF features such as deembedding based on stakeholder requests
• Work with multiple teams to design drivers for multiple RF products
• Perform HW control to deliver RF signals and measure modulated response
• Develop RF drivers for generation of low noise signals to test WiFi7 products
• Use digital modulation techniques such as QAM for low level driver development
• Develop low level USB drivers for device enumeration
• Develop drivers for HW relay control of control boards for device testing
• Perform JTAG operations on devices under test
• Use network-based protocols (SFTP, UFTP, FTP, SSH) for control board communication
• Manage HW devices such as BADC and EEPROM for control board maintenance
• Utilize C++11/14/17 features, template metaprogramming and STL
• Employ multithreading for testing and control of multiple HW devices
• Develop tools for deployment of customer OS on control boards
• Perform component and integration tests using CxxTest
• Follow Scaled Agile Framework for software development
• Create detailed design documents using PlantUML

• Situation: Increasing demand for privacy-compliant AI solutions for clients in the KRITIS and mid-market sector that need to analyze sensitive media content (audio, video, documents) without sending data to public cloud LLMs.

• Task: Design, deployment, and secure operation of a fully self-hosted AI infrastructure including a custom-built digital management platform for automated media analysis.

• Action: Architected and implemented a multi-tier platform on hardened Proxmox infrastructure with frontend (Nuxt 3, Vue 3, TypeScript, Tailwind 4), backend (Laravel 13, PHP 8.4, Sanctum), data storage (PostgreSQL 16, MongoDB 7), caching/queuing (Redis 7, Laravel Queue), AI workers (Python 3.11, Whisper, DeepFace, Librosa), scheduling (Laravel Scheduler/Cron), and local LLMs (Gemma, DeepSeek, Qwen, Mistral, LLaMA, Phi) via OpenWebUI with segmented network access, API hardening, and audit logging following BSI recommendations.

• Result: Fully GDPR-compliant, on-premises AI platform with zero data leakage to third parties.

• Task: Overall responsibility as an external Head of Cyber Security / CISO-as-a-Service for the design, implementation, and continuous improvement of ISMS according to ISO 27001, BSI IT-Grundschutz, and NIS2.

• Action: Built and managed Cyber Defense Centers (CDC) with SOC operations, integrated SIEM solutions (Splunk, Graylog), established risk-based vulnerability management (Qualys, Nessus, OpenVAS), and conducted regular infrastructure, application, and physical penetration tests.

• Result: Audit-ready ISMS for multiple clients and a 60% reduction in critical vulnerabilities within 90 days.

• Task: Design and execution of NIS2 assessments and operational roll-out plans for KRITIS operators.

• Action: Developed an online assessment tool for automated identification of individual weakness profiles, implemented ISMS optimizations, penetration testing, awareness programs, GRC suite deployment, and delivered C-level presentations.

• Result: Accelerated the consulting process by 50% and successfully prepared multiple clients for NIS2 compliance.

• Task: Incident commander for crisis response, forensics, and business recovery in ransomware attacks and APT campaigns.

• Action: Coordinated with state and federal police (LKA, BKA), performed forensic analysis (OSForensics, Wireshark, Kali Linux), executed disaster recovery and BCM strategies, and developed BTC extortion response strategies.

• Result: 100% recovery rate within defined RTO windows and sustainable post-incident security architectures.

• Action: Planned, built, and operated a hardened multi-VM infrastructure (Proxmox, 15+ VMs) with web and mail servers, Graylog, OPNsense firewalls, CRM/ERP and LLM instances, network segmentation, DDoS mitigation, automated patch management, and backup strategies.

• Result: >99.5% uptime over 20+ years and zero compromises.

• Action: Designed coordinated phishing campaigns with five levels of difficulty, developed e-trainings and webinars in a PDCA cycle, and led red and blue teams.

• Result: Phishing click rate reduced from 35% to under 5% within three campaign cycles.

• Implementing applications with Kotlin and Ktor as microservices
• Using MongoDB in the MongoDB Atlas cloud
• Asynchronous communication of services via Google Pub/Sub
• Using Kotest and MockK for unit tests
• Developing an administration frontend with TypeScript, React and Express.js
• Provisioning environments in GCP using Terraform
• Implementing CI/CD processes with GitHub Actions
• Operating scalable production and test environments in GCP with Kubernetes, Helm and Flux CD
• Monitoring environments with Prometheus and Grafana
• Providing BI data in the Google BigQuery data warehouse

• IT Senior Consultant (bank infrastructure, Active Directory, Azure, security, PKI)
• Planning, design, and implementation of cloud solutions based on Microsoft Azure / M365
• Teams, M365, and cloud services
• Vulnerabilities, threats, attacks
• Security analysis, security policy, security architecture
• Conducting meetings and presentations at various management levels
• Organizing and leading team meetings to improve internal communication
• Tools: PowerShell, Active Directory, GPO, DNS, DHCP, scripting

• Process and project management to optimize products and development processes for energy systems
• Technical risk management
• Requirements engineering and system architecture
• System FMEA of power generator units and energy storage modules aiming for generic structures
• Claims management according to Section 313 of the German Civil Code
• Regulatory environment: military and NATO standards, AQAP, VG norms

• Led the central Instore Logistics Team and oversaw support operations across 13 stores in Germany and Luxembourg, ensuring seamless coordination of logistics processes and strategic direction.

• Oversaw all merchandise management processes across stores, eCommerce, and Pick from Store, ensuring alignment, efficiency, and operational consistency.

• Analyzed staffing procedures and personnel costs across support teams, providing data-driven recommendations to the Executive Board for annual budget planning.

• Led continuous improvement initiatives including documentation, KPI development, and performance tracking to drive operational excellence through data-based insights.

• Provided technical support for new store openings and transformation projects, ensuring integration with central logistics and adherence to EU Price Indication Regulation (PAngV).

• Managed optimization and digitalization projects, including piloting digital price tags across stores to enhance efficiency and customer experience.

• Design of a new cloud service
• Requirements Engineering
• API Design (REST API, Kafka)
• Consulting on architecture, feasibility and effort estimation
• Implementation of a microservice architecture
• Implementation of a Spring Boot web service
• Development of REST APIs including business and persistence logic
• Kafka consumers and producers
• Various Excel upload/download scenarios
• Change Data Capture
• Cloud provisioning with IaC/Terraform
• Go-live with 30,000 users
• Operation, support and bug fixing for other services

Environment/tools: GitLab, JIRA, Confluence, IntelliJ, Spring Boot, Java, Docker, Terraform, AWS ECS, Postgres, Apache Kafka, SAP Datasphere, JUnit, Debezium, Apache POI, Hibernate, JPA, Testcontainers

• Development of a microservice application for calculating postings on accounts

• Development of backend components with Java or JEE, Quarkus, Kafka, Rest API

• Development of the test component with mocking frameworks (Mockito)

• Development of integration test components

• Creation of OpenAPI specification format

• Configuration of CI/CD pipeline

• Development of frontend components with React

• Design, further development and optimization of system structures

• Code review

• Java Corretto 21, JEE, Quarkus, Golang

• Reactive programming with Spring WebFlux, Project Reactor

• Git, Azure DevOps for CI/CD pipeline, YAML, Json Swagger UI, Postman, Rest OpenAPI, Kafka Streams, Kafka Connect, Log4J

• Microservices, Jira, Confluence, MySQL, Docker, Kubernetes (deployment via Helm charts)

• Spring Security, OAuth 2, JWT, Sonarqube

• IntelliJ, Maven, logging framework Splunk, Agile method Scrum, Nexus, Vaadin V24, build tool Vite

• React, React.JS, Node.js, Jess/JavaScript, Tailwind CSS, Agile method Scrum, accessibility BITV, Playwright

• Product owner and Executive Sponsor for AI Assistant trained on a knowledge base of past solution designs, RFP documents, and current product documentation
• Used by close to 100 global architects and engineers in pre-sales and post-sales
• Generates full solution documents with requirement driven architecture decisions, solution overview, diagrams, bill of material, roles and responsibility matrix
• Technologies: AI, LLM, Chat Bot, RAG, Agentic AI, Vector Databases, Public Cloud

• System administration of FreeBSD 11, 12 and 13.1 in a secure cloud software solution
• Administration of proxy servers for FITS and its clients, banks and state banks
• Administration of secure internet solutions
• Administration of secure mail solutions and mail gateways
• Administration of Apache 2.4 web servers
• Planning and maintenance of servers and network components in FNT Command
• Incident, change and ticket handling, especially troubleshooting network issues using Splunk and ARS
• Troubleshooting and log file analysis using Splunk Enterprise
• Monitoring with Nagios
• Ordering, provisioning and installation of certificates on Apache web servers, Nginx web servers and load balancers
• Hardware: HP ProLiant DL380 Gen 9 and 10, Cisco Catalyst
• Software: FreeBSD 11, 12 and 13.2, FNT Command, shell scripts, MySQL databases, ServiceNow, ARS, Splunk Enterprise 8.15