Apache Kafka Experts in Düsseldorf

• Supporting the DevOps team in Terraform-managed, multi-region AWS infrastructure to achieve environment parity.
• Developed end-to-end CI/CD pipelines using AWS CodePipeline, CodeBuild, and CodeDeploy, automating the build and deployment.
• Maintained pre- and post-deployment scripts to automate critical tasks such as database schema migrations and environment sanity checks.
• Implemented CI/CD flow specifically for hotfixes via separate Git branches, managing back-merge activities from feature branches to release branches to ensure code integrity through automated conflict resolution.
• Deployed a dedicated, lightweight sanity check application hosted cost-effectively on Azure Container Apps to run automated health and basic functional checks as a post-deployment activity triggered via pipeline.
• Investigated production incidents through code changes and AWS CloudWatch logs.
• Coordinated integration of Dynatrace APM and its APIs for monitoring purposes.
• Full stack QA strategist for a high-traffic e-commerce platform built on a layered architecture for the back-end testing of core platform services, especially the order management system in Zed and Glue layers.
• Managed automation activities, testing process, and refactoring practices.
• Responsible for framework migrations, setup, and training for new automation frameworks.
• Promoted a shift-left approach within the QA team and created the test concept.
• Participated in meetings with IT managers, business owners, product owners, and team members.
• Designed and implemented contract testing to validate API schema compatibility between the order management system and the Zed and Glue layers, reducing production-relevant breaking changes by approximately 3%.
• Led the migration to a multi-environment framework that enabled test execution across 4 country configurations from a single codebase.
• Integrated automated unit and functional tests directly into the GitLab CI/CD pipeline, reducing pipeline runtime by 32%.
• Coached and trained 5 QA engineers across Germany and Hungary in test automation, framework architecture, and best practices.
• Architected a layered backend test automation framework separating business logic, API request builders, and the database layer.
• Piloted AI-assisted testing with Playwright Agents, the Playwright MCP Server, and GitHub Copilot for automated test generation, execution, and self-healing Playwright scripts.

• Gathered and analyzed requirements in close collaboration with business departments to develop data-driven solutions and scalable PowerBI reporting infrastructures.
• Conducted detailed error analyses and optimized existing semantic and data models to ensure a robust data architecture and high data quality and to improve PowerBI reporting.
• Developed and implemented scalable ETL processes for data preparation and integration.
• Built a wiki for table and view descriptions as well as PowerBI PowerQuery and KPI documentation to ensure a consistent understanding of data structures and key performance indicators.

(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.

• Creating interfaces between the legacy platform and the new container solution
• Coordinating required contributions from line units
• Moderating regular status meetings with the software vendor
• Minimally invasive conversion of TWS scheduling from the old to the new platform
• Environment: IBM Mainframe, DB2, CICS, MQ, Red Hat Linux, Oracle, Kubernetes, Kafka, Helm, GitLab, Jenkins

• Contributed to the development of an advanced RAG AI Chat application that integrates multiple LLM models, enabling users to seamlessly switch between models based on specific tasks. This improved the user experience by providing tailored, efficient solutions for various use cases, such as event scheduling, booking systems, and complex task management.
• Participated in designing and implementing a robust backend architecture using Spring AI, enabling advanced AI-driven capabilities like intelligent task automation, language processing, and contextual recommendations. Leveraged Spring AI Tools and Advisors to enhance the performance and decision-making of the AI models.
• Collaborated on the integration of vector databases to support embeddings, enhancing the app's ability to understand user queries and perform actions based on complex, real-time data inputs.
• Contributed to the development of a seamless, user-friendly front-end interface using React with TypeScript support, ensuring a modern, responsive, and scalable user experience across platforms.
• Assisted in implementing state management with Redux RTK for efficient data flow and real-time updates, optimizing the overall user experience in dynamic scenarios such as scheduling and task management.
• Partnered with stakeholders to define feature requirements, helping ensure that the app could scale to meet evolving business needs and integrate with other systems like calendar and email services. Worked alongside cross-functional teams, including data scientists and UI/UX designers, to fine-tune AI models and ensure alignment with project goals.
• Contributed to ensuring end-to-end system performance, security, and compliance by helping integrate authentication mechanisms, role-based access control, and secure communication protocols in both backend and frontend layers.

Technology Stack and Key Contributions:

• Java / Spring Boot / Spring AI: Developed backend services leveraging Spring AI for intelligent responses, task automation, and complex workflows.
• React / TypeScript: Built intuitive user interfaces with React and TypeScript, ensuring a smooth and scalable frontend.
• Redux RTK: Managed application state with Redux RTK for optimized state management, enabling dynamic, real-time data updates.
• Vector Databases: Integrated vector databases (pgVector) for embedding support, improving AI model performance in handling complex queries.
• PostgreSQL / Redis: Managed persistent and temporary data with relational and in-memory data stores, ensuring data integrity and speed.
• Kafka: Utilized Apache Kafka for event-driven communication and seamless integration between microservices.
• Spring Security: Ensured the security of backend services with robust authentication and authorization mechanisms.
• CI/CD & DevOps: Integrated continuous integration and deployment pipelines to ensure rapid and secure deployment of features and updates.

• Migration of backups and complete workloads to AWS and Azure, including setup and management of AKS & EKS clusters.
• Automation with Terraform & ArgoCD, CI/CD pipelines implemented with GitLab.
• System monitoring on OpenShift 4 (on-premise) with Grafana & Prometheus, use of CloudWatch and X-Ray for analysis and logging.
• Building and maintaining secure network infrastructures (VPCs, SGs, WAF, ACLs), integration of Azure Log Analytics.
• Close collaboration with infrastructure and development teams, maintenance of technical documentation with Confluence, ticket handling via Jira, and promoting cloud knowledge within the company.

• Project Manager for banking projects
• Management and coordination of the projects 'XONTRO T7 Migration' and 'UNO – Unified for New Opportunities'. Management of international stakeholders, preparation and leadership of steering committees, and coordination between departments, exchanges, and external partners.
• Project management of the strategic projects 'XONTRO T7 Migration' and 'UNO – Unified for New Opportunities'
• Management of international stakeholders including exchanges, custodians, and external project partners
• Coordination of functional and technical test activities at the exchanges between trading, IT, accounting, and mid-/back office
• Facilitation of steering committees at management level
• Preparation of decision papers, status reports, and risk analyses
• Conduct analyses in the areas of reporting (compliance, regulatory reporting, etc.), taxes on securities transactions & custody accounts, process analysis
• Enforcement of required requirements/specifications
• Coordination between business, IT, operations, and external market participants
• Coordination and alignment with external market participants, service providers, exchanges, and other project stakeholders

• Introduction of giro card with Visa Debit card payment function (Combocard) for Commerzbank
• Support for the Card Processing Team (card processing; Clearing & Settlement incl. Dispute Management teams) in project work
• Creation of requirements for the Clearing & Settlement team, Authorization team (AZ) and Card Production team (KP) as part of a requirements catalog
• Requirements engineering (requirements management) with business contact person
• Participation in workstream meetings between VISA Inc., SRC Security Research & Consulting GmbH, Commerzbank AG and consulting firms (PwC and Senacor Technologies AG)
• Sprint planning with Jira tickets of type Task and use of Confluence
• Creation and presentation of weekly status reports for the Clearing & Settlement, Dispute Management and Reporting & GUI workstreams
• Coordination with network and file transfer teams for connection tests of new interfaces, e.g. setup of host keys, use of VPN or sipnet connections
• Coordination of the delivery of test files, e.g. exchange rates (FX rates; TC 56 of VISA rates), VISA Debit and Credit transactions (format Base II) and EANSS/ISS Base II clearing files to the Debit Clearing System (DCS)
• Conducting coordination meetings on the use of Visanet Settlement Service (VSS) and PSD2 reports and payment traffic statistics (ZVS)
• Organizing workshops with FiServ (First Data) on Dispute Management and complaint handling
• Setup and maintenance of Open Point List (OPL) in Confluence
• Technologies/methods: Jira, Confluence, giro card, VISA Debit card, payments, Kanban board, BIN, routing, CIQ, VPAY, ScalaTest, Dispute Management

• Creation of business and technical concepts as well as support for enterprise architecture management as part of the migration to the Adesso standard insurance solutions and the renewal of surrounding systems

• Interface definitions

• Business analysis and creation of the business concepts for input management and sales

• Creation of architecture guidelines and processes

• Processing technical and business decisions in the architecture board

• Definition of service processes and system management aspects

• Creation of the technical target operating model

• Creation of an integration architecture for AI/LLMs from the providers Commasoft and Insiders

• CommaSoft (Alan) webpages and web services

• Insiders for Smartfix based on web services

• Creation of a question catalog for a security/regulatory check.

• Analysis of threats using threat modeling / STRIDE incl. creation of a set of measures to secure the systems

System environment: Jira, Confluence, Java, Enterprise Architect, VAIT/DORA, KritisV, GDPR, IT ServiceMgmt, Adesso Ecosphere and Insure Health, DoPIX and successor product, SmartFix, SmartFlow, Zabas, Kolumbus, Clarc archive, BiPRO, AI / LLM, MS Azure, AWS, TOM/FMO

• Analysis of the possibility of transferring market location data to a separate microservice in an overarching web portal
• Development of a more user-friendly target process based on the current process in coordination with users
• Coordination of the related architecture concept with architects/developers
• Coordination of the related epics and user stories with the relevant business departments
• Backlog prioritization and project planning (including effort estimation)
• Testing and acceptance of implemented user stories
• Technologies/tools used: MS Office, Jira, Mural, Kotlin, React, GitHub, MS Azure, SQL, Postman, XML, JSON, Kafka, Balsamiq, BPMN

• Built and launched the AI-powered “E-Invoice Corrector,” an intelligent system for validating and correcting invoices, using Python, FastAPI, and machine learning. The system is now live at Fintom8.
• Converted the Corrector into a fully functional API, published with Swagger documentation for easy access and integration by internal and external consumers.
• Designed, experimented with, and optimized advanced LLM prompts and meta-prompting strategies to improve automated reasoning, error correction, and decision-making in agent workflows.
• Wrapped and integrated existing APIs within the Google Agent Development Kit (ADK) framework to enhance automation capabilities and conversational AI workflows.
• Implemented comprehensive unit testing using pytest and unittest, and employed breakpoint debugging (VS Code, pdb) to ensure code reliability, maintainability, and smooth runtime execution.
• Utilized Pydantic and Tabulate for structured data validation, API schema management, and clear tabular data representation in testing and debugging workflows.
• Pursuing the Google Cloud Professional Certificate.

• Design, development, and execution of load and performance tests for the PRISMA project
• Use of Apache Jmeter, Gatling, Apache ActiveMQ, Jms/Tibco Ems, SikuliX, Jython, Amazon AWS, PAN-Client
• Methods: load tests, test automation

• Visualization, search, and maintenance of various types of master data, providing them via a REST API, and implementing a variety of import and export formats.

• Implementation, architecture, project management.

• Technologies and tools: Angular (Signals, Signal Store, swagger-codegen, standalone components), Java, PostgreSQL, ActiveMQ, JavaScript, Spring Boot (Spring Core, Spring MVC, Spring Data/JPA via Hibernate, Spring Security, Spring Modulith), JUnit, Flyway, QueryDSL, GraphQL, REST API, Node, npm, Maven, SonarQube, GitLab CI/CD pipelines, Docker, Nexus, OpenAPI + Swagger UI, Keycloak, OAuth2, OpenID Connect, IntelliJ IDEA, Jira, Confluence.

• Setting up and enhancing an international subscription management system

• Migrating and decommissioning a Hybris-SAP system and integrating Zuora

• Implementing numerous interfaces to various systems (external and internal)

• Setting up and improving monitoring with Grafana, Prometheus, and Databricks

• Introducing logging with Loki

• Implementing business requirements using jQuery, Thymeleaf, Spring Boot, Java, Go, and Python

• Adjusting and extending the GitLab CI pipelines

• Setting up and extending infrastructure as code with Terraform and ArgoCD on AWS

• Setting up and running E2E and performance tests

• Expanding the Databricks business intelligence solution to provide various KPIs

• Responsibilities: Architecture, DevOps, development, unit tests, coaching employees and apprentices, E2E, smoke, and integration tests, agile methods consulting (Kanban, Scrum)

• Technologies and methods: Java, Go, Kotlin, Node.js, Spring Boot, SOAP/REST, Quarkus, Thymeleaf, Vaadin, Slack, Jira, Confluence, IntelliJ, GitLab, SQS, Kafka, AWS, Kubernetes, Terraform, Maven, Gradle, GitLab CI, Databricks