Linux Experts in Stuttgart

• Designed a migration strategy for WLS applications to BKA Cloud and Stack IT

• Created a hybrid cloud for internal testing and development with Kubernetes

• Transformed the IT landscape from an outdated monolithic architecture to a cloud-based architecture

• Integrated new CI/CD processes using Azure Pipelines

• Quadrupled the processing throughput for personnel security checks

• Migrated personnel security screening applications to Docker-based applications

• Implemented CI/deployment pipelines using Azure DevOps

• Environment: Java Springboot, Kubernetes, Oracle Weblogic, OpenID, Camunda, JUnit, TOGAF

• 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

Designed and developed an AI-powered automation platform using n8n to analyze social media niches, identify target audiences, and automate marketing strategy generation. The solution combined AI agents, workflow orchestration, and data analysis to automate research processes and generate data-driven insights.

• Designed and implemented complex automation workflows using n8n
• Developed AI-powered analysis agents for market and audience research
• Integrated multiple APIs and AI services into automated workflows
• Built automated market, competitor, and target audience analysis pipelines
• Leveraged Large Language Models (LLMs) for information summarization, classification, and prioritization
• Containerized and deployed the platform using Docker

Technologies: n8n, AI Agents, OpenAI APIs, Prompt Engineering, LLMs, Docker, Linux, REST APIs, Webhooks

• Investigation PoC and exchange and refinement of an existing cloud and IoT power plant control solution for certificate management of renewable energy power plants (solar, wind, biomass and others) of the largest European renewable energy power plant operator in this field, including investigation of the IoT devices used in the field and their integration and network connection with the aim of automated PKI key management.
• Messaging with Kubernetes for large API-connected enterprise applications
• Risk and Attack Vector Analysis, Software Quality & Bug Assessments
• Agile Workload Scheduling via Jira & ConJluence
• Evaluation of message streams Pub/Sub for MQ and KaJka.
• Various tests with “best design approaches” regarding resilience patterns such as Circuit Breaker Designs, Throughput Measurement and Monitoring, Bulkhead Governors - for robust EA design
• Integration of API Management with IBMs API Connect to Kubernetes - for agnostic Microservices API Management Designs. Google Apigee
• Solution Health Check Approaches for Load Burst Situations + Remedy
• Research and investigation of available potential subcontractors in the coordinating role as Solution Manager. CIS20 Controls.
• Dread and Stride Security Assessments.

• 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 SaaS platform for esports teams with roles, planning, statistics and billing
• Design and implementation of the architecture, external API integrations and operations
• Stack: Laravel 13, React 19, TypeScript, PostgreSQL, Redis and Stripe

• 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

• 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