Spring AI Experts in Germany

• Recurring problem in my own AI-assisted projects: requirements analysis, use cases, and architecture decisions can be created quickly with AI support, but remain difficult to follow and scattered across Markdown files – knowledge is lost as soon as it is no longer in the context window. arknet turns requirements engineering and architecture knowledge into structured, verifiable data instead of plain text: requirements, use cases, and architecture decisions form a consistently linked knowledge graph, traceable from requirement to architecture decision – queryable by both people and AI agents. Technically based on RDF/OWL and a custom MCP server.

• Result: Working MCP daemon, Docker image published automatically to GHCR, nine hexagonal modules, eleven ADRs (including an Open-Core licensing model). Requirements engineering and Ubiquitous Language hexagons are active. Public as a Community Edition under Apache-2.0 since 07/2026 (github.com/kogn-io/arknet), together with the Claude Code plugin and GHCR image; Open-Core model.

• Label: Java, Maven, RDF, RDF4J, OWL, SPARQL, Model Context Protocol, Spring AI, Docker, GitHub, Git, Claude Code, Obsidian, DDD, Hexagonal Architecture, ArchUnit, JUnit, AssertJ, Interface Development, Software Architecture, Continuous Integration, Knowledge Management

IT consulting, analysis, architecture design, new and further development, code review, test automation, continuous integration, continuous delivery in backend and frontend areas for Automotive Project Instavalo.

Frontend:

• Implementation of UI components according to specifications, especially style guides and responsive design eith React and Typescript
• Component testing
• Code documentation
• CI/CD with Gitlab Pipeline

Backend / IoT:

• Analysis and architectural design with AWS Greengrass IoT on Edge Devices
• Setting up Microservices containers with Docker Compose on Edge device with AWS Greengrass and AWS IoT IAM, Token Exchange Service, Ansible
• CI/CD with Gitlab Pipeline, Terraform, AWS ECR
• Logging with Fluentbit Lua Language for AWS Cloudwatch
• Python Lambda for AWS Greengrass Recipe deployment on Edge Devices
• Implementation of test-driven development with JUnit, Mockito, and code Coverage
• Jacoco
• Definition of REST interfaces with OpenAPI / Swagger
• Development and enhancement of software based on Java Quarkus, Typescript NestJs NodeJs and Python
• Authentication and authorization in Aws IAM
• Development of REST and gRPC interfaces for the frontend and backend
• Implementation of Maven dependencies with DevSecOps OWASP
• Spring AI, Jetbrains AI Assistant, Junie, Github Copilot, Claude Code, Agents, Skills, Command, Hooks, Subagents

• 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.

• Analysis
• Consulting
• Software design
• Development
• Automation
• Testing
• Deployment
• Architecture, development and deployment of various proof-of-concept applications around the integration of current AI interfaces including conversational, realtime voice, images and videos
• Developed best practices for working with agentic systems and AI in practice
• Created code templates

• Analysis of existing microservice structures and integration into the event-driven architecture
• Design and implementation of prototypes
• Introduction of structured workflows and embedding in a solid testing strategy
• Team: small specialized team (3-5 people) from analysis to implementation readiness
• Documentation of architectural decisions and definition of interfaces
• Integration of the event-driven pipeline into the existing landscape
• Technologies: Kafka, Docker, Microservices, Event-Driven Architecture, Java, Liquibase

Java 21 · Spring Boot 3 · Keycloak · PostgreSQL · Docker · Nginx · GitHub Actions · DigitalOcean · React 18 · TypeScript · Plasmo

• Architected and shipped a production-ready Job Application Tracker end-to-end: REST API with 5-stage workflow, pagination, sorting, and dynamic filtering — full ownership from design to live cloud deployment on DigitalOcean.
• Implemented production-grade identity management: OAuth 2.0 / OpenID Connect / JWT / RBAC via Keycloak, applying Hexagonal Architecture and DDD principles.
• Built automated CI/CD pipeline (GitHub Actions); containerised with Docker; Nginx reverse proxy with path-based routing and SSL termination.
• Developed a Chrome Extension (Plasmo framework, Manifest V3) that auto-fills job applications directly from LinkedIn into the tracker — demonstrates full product thinking across backend API and browser client.

• Tech Stack: Java 17, Spring Boot, Microservices, REST, GraphQL, Spring AI, Jenkins, Docker, Git/Bitbucket, JUnit, Splunk
• Led a team of 6 to deliver policy, claims, and onboarding modules serving 50k+ users, maintaining 99.9% uptime
• Cut release cycle time by 35–40% by automating CI/CD with Jenkins and Docker
• Implemented trunk-based branching in Git/Bitbucket
• Integrated 10+ REST APIs and streamlined customer workflows, boosting process automation by 40%
• Increased system stability with proactive Splunk alerting and runbooks, reducing outages by ~25%
• Driven quality with JUnit tests (92% coverage) and code reviews; enforced standards with static checks such as SonarQube

• Responsible for the new development of billing and auditing software for prescriptions (prescriptions) to fully check and evaluate e-prescriptions for correctness (content, billing)

• The system consists of several contexts that run as services (Docker containers):

• Checking and processing data deliveries via FTP and email

• Managing invoices, clearings, advance payments and deductions

• Managing and running audit rules and audit folders

• Evaluations based on Metabase

• Developer Stack: Kotlin, Vue 3 / Vuetify 3, ANTLR, Spring Boot 3, REST API, Gradle, Docker, GitLab, PostgreSQL, Kafka, Keycloak, Scrum, Grafana, Loki, Testcontainers, Prometheus

• Led development activities for enterprise applications, managing design, planning, and delivery to meet organizational goals.
• Constructed and deployed microservices using Java/JavaEE, Kotlin, Spring Boot, Kafka incorporating synchronous and asynchronous communication, achieving a 95% on-time delivery rate.
• Developed microservices in Golang utilizing frameworks such as Gin, GORM, and Viper for high-performance applications.
• Maintained RESTful and GraphQL APIs, enabling seamless integration with enterprise applications.
• Leveraged gRPC for secure, efficient service-to-service communication in microservices, reducing latency.
• Used SQL databases (MySQL, PostgreSQL) and NoSQL databases (MongoDB, Redis).
• Integrated publisher-subscriber systems and message queue architectures (SQS, Kafka).
• Configured secure authentication and authorization systems (OAuth 2.0, OpenID Connect) using AWS Cognito and Spring Security.
• Architected scalable patterns like API Gateway, Circuit Breaker, Saga, CQRS, and Event Sourcing to enhance reliability and performance.
• Built middleware solutions integrating complex APIs and third-party services for seamless system interactions.
• Achieved cloud-native architectures with AWS services, including S3, EC2, Lambda, API Gateway, RDS, DynamoDB, SNS, SQS, EKS, ECR, and ECS.
• Delivered a centralized CI/CD pipeline, reducing deployment time by 80% through automation and standardization.
• Integrated observability tools such as Prometheus, Grafana, Datadog, and CloudWatch, improving monitoring and troubleshooting capabilities.
• Automated IaC provisioning with Terraform, ensuring consistent and scalable environments across development, testing, and production.
• Enhanced logging and visualization using the ELK stack (Elasticsearch, Logstash, Kibana).
• Optimized release processes, ensuring efficient and error-free deployments, resulting in a 30% reduction in production bugs.
• Lifted services to the cloud, transitioning legacy systems to a cloud environment to improve scalability and performance.
• Automated infrastructure tasks with Python, streamlining workflows such as S3 file uploads and SQS event handling.
• Crafted Python scripts to test AWS services locally using LocalStack, achieving 98% accuracy.
• Designed and architected large-scale, scalable enterprise applications, performing end-to-end, unit, and integration testing, reducing production bugs by 25%.
• Designed and developed web applications using Angular, HTML, CSS, and JavaScript.
• Integrated advanced security measures into the DevSecOps pipeline, including SAST with SonarQube, DAST using OWASP ZAP, vulnerability scanning with Snyk, container image scanning via Trivy.
• Mentored 5+ junior developers in Java, Kotlin, and microservices, boosting team productivity by 20% within six months.
• Facilitated workshops on modern architecture, DevOps, and cloud integration practices, enhancing team proficiency.

• Developed Skalman’s Food & Sleep Clock web app with a digital assistant that reminds users about medication intake, meals, movement breaks, and other daily routines.

• Implemented personalized meal suggestions and simple recipes with support for allergies and special diets, integrating AI to generate tailored meal ideas.

• Built Flight Booking App using React and Axios for the front end, Spring Boot with JPA and MySQL for the back end, and implemented user authentication, form validation, and booking logic.

• Designed and built a chatbot that accepts natural language queries and generates intelligent responses using OpenAI’s language model.

• Developed MarketPlace_AP with React and Axios on the front end, Spring Boot with JPA and MySQL on the back end, enabling users to discover services or products, with authentication and form validation.

• Created a Meeting Calendar page allowing users to schedule, view, and manage meetings using React, Axios, Spring Boot, JPA, MySQL, and authentication with validation.

• Created a Todo List Manager: built a REST API with Node.js, Express, and MongoDB; developed a React front end featuring status toggling and filtering; deployed on Heroku and integrated with GitHub for CI/CD.