Linux Experts in Essen

• Operation and further development of the network and security infrastructure.

• Monitoring, analysis and resolution of network and security incidents.

• Cross-department collaboration with other specialist teams for operations, further development and reporting.

• Firewall vulnerability analysis.

• Firewall rule approvals.

• Troubleshooting IP communication issues in the network and firewall infrastructure.

• Security-critical IT infrastructure, processing of personal data, compliance with legal regulations.

• Products: Palo Alto Networks Firewalls, Cisco ACI, Checkpoint Firewalls, F5

• Technologies: SDN, SDWAN, Cisco EPIC, Cisco ACI

Gronic Ident & Sign

Core technologies: Android, Jetpack Compose, Retrofit, Regula Document Reader, Adobe Sign

Android app on dedicated devices for identifications and electronic signatures at the PoS

• Training AI models, evaluating images and text UI/UX, turning the provided data into insights through OpenAI Feather as part of the machine learning workflow

Technologies: OpenAI Feather

• Management of IT with 10 employees, including budget and personnel responsibility.
• Harmonization of the Navision systems in Germany, Switzerland and Austria.
• Connection of the ERP systems in Switzerland, Austria and Italy to the central Microsoft Power BI systems in Germany.
• Rollout of a new firewall at 10 locations in D, CH and A.
• Evaluation of a new DMS.
• Migration to Windows 10 / 11.
• Transformation of 9 countries into ONE Europe.
• Start of NIS2 implementation in 5 European countries.

• Delivered MVP-focused full-stack architecture for a health-sector client: Vite/React frontend, backend services on Google Cloud Run, and Supabase for database plus IAM/authentication.
• Supported product requirements engineering and prioritized cost-aware workload placement, implementing browser-side/edge computation where feasible before moving logic to backend services.

• Transition of Microsoft Azure operations to BTC AG
• Responsibility: budget of €60k
• Staff: leadership of 5 people
• Tools: Office 365, JIRA, Confluence

(Maternity/Parental Leave: July 2023 – Aug 2024)

• Domain: Payment Domain | Client: Telefonica Germany
• Project: General Payment Service

The General Payment Service is responsible for processing of online payments via external payment service provider like Safer pay and PayPal

• Developed Design of Use (DOU) and interface contract documentation, ensuring clarity and compliance across system integrations
• Designed and delivered REST/SOAP web services with Spring Boot and Spring Data JPA, publishing Swagger contracts through WSO2 API Gateway to improve accessibility and governance.
• Spearheaded the on-premises to AWS Cloud migration, re-platforming from Oracle to PostgreSQL on AWS RDS and deploying services on EC2, improving scalability and cost efficiency.
• Containerized microservices using Docker and orchestrated deployments with Kubernetes, streamlining deployment pipelines and improving system reliability.
• Implemented proactive monitoring and logging via AWS CloudWatch and Kibana, ensuring stability and performance during cutover.
• Enhanced collaboration through code reviews and peer reviews, promoting maintainability and clean coding standards.
• Strengthened quality by writing comprehensive JUnit tests and preparing detailed test cases enabling early defect detection
• Delivered automated API testing with Ready API, Postman, and SOAPUI, and conducted performance testing with JMeter, ensuring reliability in high-transaction environments.

• Optimization of the transmission media of the data links in the Ruhr area
• Configuration/expansion of switches and routers for an autonomous system AS
• Improve the network protocols used Layer 2/3 (OSI model), RSTP, broadcast, etc.
• Laying cables, crimping, antennas, routers, switches
• Maintenance, expansion, selection and prioritization of troubleshooting measures for network monitoring (PRTG, The Dude)
• Organization and new connection of another BGP peering, data center, NGN fiber optic
• VPN IPSec site connections for 6 sites with PFSense, Fritzbox
• Configuration of WLAN devices (Mikrotik, UBNT

Label: TCP/IP, VLAN, BGP, OSPF, MPLS, VPLS, routing protocols, WLAN, EoIP, PPPoE, routing, SNMP, DHCP, DNS, NAT, native IP, VLAN, Ethernet, VoIP., switches and routers from: Nortel, Cisco, MikroTik, UBNT., network management systems: The Dude, PRTG, UISP

• Company FROX (Schweiz), end customer: Bundesamt für Informatik und Telekommunikation.
• Consulting and development. ITSM Suite, development of a semi-generic REST API interface solution. Performance tuning.

• CHG Meridian AG is a financial company focused on leasing in the areas of IT technology, logistics and medical technology and is regulated by BaFin. One part of the company is Return to Remarketing, where devices delivered to the technology center (notebooks, smartphones, tablets, etc.) are prepared for resale. The project I supported was responsible for enabling damage assessment of returned lease devices, documenting them visually in the form of pictures, enabling invoicing for the customer, and making the pictures available via the in-house customer platform. This was achieved through a combination of in-house development within the internal development department and the use of SaaS products. The second project was the transition of SaaS tendering software, purchased by the business unit, into the operations of the CHG IT department. Evaluation of security questions in relation to BaFin requirements, development of an authorization concept, implementation of single sign-on, documentation of the application in the CHG systems (CMDB, iKnow, etc.) and handover into operations.

Used technologies and methods: NIS2, DORA, agile software development, Scrum, Kanban, ServiceNow, SaaS, MS Teams, MS SharePoint, Active Directory, Entra ID, CMDB, incident management, change management, request management, service level agreement

• The goal of Afworki GmbH IT-Consulting is to make small and medium-sized companies more competitive by overcoming challenges in digitalization, automation, and data management.

• Tailored technology, strategy, and specialist consulting designed to meet the individual needs of each company.

• Analyzing the company's current situation and developing the best possible solution together with the client.

• Using both agile and classical IT project management methods to deliver projects on time and within budget.

• Focusing on automating and orchestrating all data flows in a data warehouse to create a unified and standardized data foundation.

• Considering the dependencies between IT and business to achieve sustainable positive effects.

• Employing modern strategies and tools specifically tailored to the company's needs.

• Supporting digitalization, the introduction of agile working methods, and the creation of up-to-date reports and analyses.

• Objective: streamlining management and enabling well-founded, data-driven decision-making.

• Led the subproject for implementing Vulnerability Response as part of DORA
• Documented the current processes in compliance, risk & security
• Created the functional design for introducing application, infrastructure, and cloud vulnerabilities
• Agile management of the integration service provider, the technical department, and the company's cross-functional teams
• Integrated the V scanners Tenable, Qualys and Defender, as well as NVD and CISA/KEV
• Integrated GitLab Ultimate for importing and processing SBOMs
• Developed automation rules to match scan results with CIs in the CMDB, assign vulnerabilities and remediation tasks, handle approvals (false positives, exceptions) and closures
• Calculated multiple risk scores and priorities
• Defined dashboards and reports (Workspaces, Performance Analytics)
• Aligned the new processes, especially to improve the CMDB data quality (according to CSDM)

• Design and implementation of a system for controlling the complete process of installing, removing, and replacing electricity meters by external service providers for an energy supplier

• Automated retrieval of orders and available devices through defined interfaces (e.g. from SAP)

• Orchestration of the process steps (assignment of meters, processing of meter data, transfer of updated information back to the source system) through a Spring-Boot backend

• Provision of a React-based web client for operational tracking and control of orders, e.g. to continue failed process steps or resend notifications

• Development and implementation of test concepts for complex, multi-layered systems
• Creation of regular management reports and presentations for stakeholders and clients
• Technical and disciplinary leadership of international test teams (coordination, coaching, resource planning)
• Responsibility for quality assurance across multiple test levels (unit, integration, system, and acceptance tests)
• Design of test cases and test plans in Azure DevOps; ensuring traceability and coverage
• Use of BDD approaches (Gherkin/Cucumber) to prepare test automation
• Building a test automation architecture with Playwright and integrating new tests into CI/CD pipelines
• Performing API tests (REST) and tests for mobile/PWA applications
• Setup and maintenance of test environments across multiple stages (integration, QA, UAT, pre-production)
• Test data management (synthetic and production-like data), ensuring consistency and reproducibility
• Collaboration with DevOps teams for containerization (Docker/OpenShift) and CI/CD integration
• Working under SAFe & Scrum, closely coordinating with product owners and DevOps teams
• Active participation in PI plannings, sprint reviews, and retrospectives
• Promoting an agile QA culture through coaching and knowledge sharing
• Introducing scalable test automation with Playwright → significant reduction of manual testing efforts
• Increasing test transparency through clean defect and reporting management in Azure DevOps
• Improved release quality through an end-to-end QA strategy and automated regression tests
• Strategic leadership of Trikolon Consulting GmbH and responsibility for finance, personnel, and business development