Jakarta EE Experts in Berlin

• Developed and deployed microservices in Kotlin and Spring Boot, integrated AWS Secrets Manager to secure credentials and decreased network calls using Spring cache.
• Refactored Kafka consumer using Spring Kafka with semaphore-based backpressure to cap records and keep heap memory stable under spikes; switched to batch upserts to cut down on database invocations; added Testcontainers integration tests for Kafka and database to pave the way for future changes.
• Automated the financial reconciliation workflow in Spring Boot (Kotlin) using Spring Scheduler, transactional boundaries, JPA/Hibernate on MySQL, and Flyway migrations, saving the accounts team 16+ hours per week.
• Designed and dockerized payments end-to-end test framework in Robot (Python) with reusable keyword libraries and profiles; integrated with GitLab CI (JaCoCo XML and HTML reports) to accelerate releases and lift code coverage to 80%.
• Implemented end-to-end observability on Datadog by instrumenting services with Datadog APM, correlating metrics and logs, provisioning dashboards, and creating monitors with burn-rate alerts and anomalies to harden reliability and give stakeholders clear visibility.

• Designed and developed AI-powered document processing solutions using Python, OCR, NLP, and Large Language Models (LLMs) to automate extraction, validation, and classification of financial documents, reducing processing time by 75%.
• Built intelligent multi-stage workflow automation pipelines integrating AI services, machine learning models, and enterprise systems to streamline financial operations and improve data quality.
• Developed reusable AI-driven transformation frameworks capable of processing structured and unstructured document formats (XML, CSV, JSON, TXT, DAT) and normalizing them into unified business schemas.
• Designed and developed Python-based REST APIs and backend services supporting enterprise finance applications and high-volume data processing workloads.
• Built scalable data synchronization pipelines between Oracle CFIN and SQL databases, incorporating machine learning models for cash-flow forecasting and AP/AR anomaly detection.
• Architected and deployed Apache Airflow workflows to orchestrate AI-powered data pipelines, automating end-to-end processing from document ingestion through financial system integration.
• Led the migration of critical enterprise integrations from MuleSoft to Python-based services, improving maintainability, performance, and operational flexibility while preserving complete data integrity.
• Managed the full API lifecycle including solution design, implementation, documentation, deployment, monitoring, and production support for mission-critical financial systems.
• Collaborated directly with finance stakeholders to identify business challenges, define solution requirements, and deliver measurable operational improvements through automation and AI-driven workflows.
• Worked closely with cross-functional engineering and business teams to rapidly iterate on features, improve processes, and drive successful adoption of AI-enabled solutions.
• Provided technical leadership through architecture reviews, technology decisions, code reviews, and engineering best practices across integration and automation initiatives.
• Mentored developers, established coding standards, and contributed to improving software quality, maintainability, and delivery effectiveness across projects.
• Provided production support during critical month-end and quarter-close financial processes, performing root-cause analysis and implementing rapid fixes to ensure system reliability and data accuracy.

• IT training in theory and practice for IT specialists in application development and system integration

• Provide the Price Listing Service team with prices for all cars and vans in different markets
• Adapt market-specific requirements such as taxes, government subsidies, campaigns
• Import and synchronize new prices for all new and existing cars and store them in the Redis datastore
• Support our product and on-call duty
• Daily business, development of new features, bug fixing
• Pair programming, code review, mob programming
• Develop POCs for new ideas
• Maintain and extend the backend
• DevOps tasks
• Run Kubernetes updates
• Adjust and further develop Kubernetes resources
• Develop and adapt Helm charts
• Adapt and update ArgoCD
• Maintain, adapt, and improve CI/CD

• Development and rollout of a browser-based platform for camera streaming, augmented reality (AR), and visual computing
• Device-independent camera streaming for smartphones, tablets, desktop PCs, as well as VR and AR headsets
• Ensuring GDPR-compliant hosting in Open Telekom Cloud and other sovereign cloud providers
• Intuitive visual and collaborative features to increase efficiency and integrate smoothly into existing business software

• Maintenance, further development, modernization and testing of the OK.VERKEHR specialist application, a monolithic Enterprise Java solution (with approx. 3,5 Mio LOC) for vehicle registration and driving license authorities
• Design, development, testing and maintenance of end-to-end workflows (dialogs, backend services and persistence layer, test suite) for new driving license applications, changes/extensions to driving licenses, management of parking permits and truck driver cards
• Development and maintenance of web services for communication between local traffic authorities and the Federal Motor Transport Authority, FAER register, TÜV testing centers and driving schools
• Performance optimization and targeted refactoring for the future migration to a cloud architecture and the addition of a new web client (Vaadin)
• 3rd-level support for customers during ongoing operations

• Subject matter expert for the client on modeling and developing Camunda BPMN 2.0
• Development of new features and APIs, and coordination of tasks
• Design and development of RESTful APIs with Swagger (code first)
• Creation of target designs, high-level concepts, and requirement specifications
• Analysis and evaluation of alternative solution approaches
• Integration of external IT systems (ANUBIS, SES, ZPS) via Google GCP Pub/Sub and RESTful web services
• Pair programming, code reviews, and collaboration with API product owners
• Consulting on transforming legacy BPMN workflows and configuring Camunda BPM
• BPMN and DMN modeling and implementation in short iterations
• Operational support, bug fixing, and knowledge documentation
• Use of TDD, static code analysis with SonarQube, and integration tests
• Automation of test cases in Java and analysis of stack traces/logs on GCP-PROD
• Identification and execution of test data and documentation of test results

• Developed high-performance APIs for SDK backend on JavaEE Web, iOS, and Android, improving application performance and scalability by 30%.
• Led system design, tech stack planning, and development, ensuring 98% uptime with strong code quality and automated tests.
• Implemented CI/CD pipelines with Jenkins and GitHub Actions, reducing release cycle time by 40%.
• Deployed cloud-native applications on AWS EC2 instances, ensuring 99% uptime and optimized performance.
• Delivered clean code with full unit, component, and integration test coverage, reducing defects by 25%.
• Collaborated across engineering, QA, and product teams to deliver secure, reliable solutions.
• Mentored team members, increased development efficiency by 20%, automated routine tasks, and contributed to hiring, growing team capacity by 15%.

Training course with exam for Spring Certified Professional.

• Environment: Spring Boot 3, Spring Framework 6, IntelliJ