PlantUML Expert 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

• Overall responsibility for the project lifecycle from scope definition to completion
• Close collaboration with platform teams, IT leaders, and external service providers
• Application of SAFe principles and structured sprint work
• Creation of a migration roadmap with clear milestones
• Monitoring of the lifecycle: onboarding, repository migration, replication of permissions, and system tests
• Visualization of the architecture with PlantUML and Gliffy as well as documentation in Confluence
• Regular status reports and running knowledge transfer sessions

Refinement of epics and user stories to achieve a higher degree of automation in CRM usage. Testing of new Discountsystem

Conceptual design and implementation of a modular customer portal based on Laravel.

The focus was on defining a maintainable system architecture with broad use of Domain-Driven Design principles (within the Laravel architecture), introducing automated quality assurance processes (test strategy, CI integration), and preparing an auditable operation (logging, traceability of changes) in an AWS-based infrastructure, taking IT security standards according to NIST and process requirements according to ISO 9001 into account.

Achievements:

• Analysis and structuring of business requirements in close coordination with stakeholders
• Documentation of the system architecture and infrastructure incl. change and release management
• Design and implementation of an interface for integrating SAP systems
• Planning and implementation of automated tests for quality assurance
• Implementation of security and compliance requirements, including SBOM generation, software license management, and QA processes
• Technical consulting and support for the internal IT team
• Introduction and establishment of AI-supported development processes (Spec-Driven Development), including AI-readable specifications, integration of AI instructions into the development environment, and training developers for productive use

Technologies and tools: SAP, Docker, ddev, PHP 8.4, Laravel, Filament, C4 Model, Architecture Decision Records (ADR), Mermaid, PlantUML, Spec-Driven Development, Claude, GitHub Copilot, Codex

I implemented a Zero-Trust architecture for robust, military-grade maritime container mini data centers based on VMware & Tanzu to support containerized GIS workloads for ground forces. The main focus was on securing communications, workload protection, and data access in contested electronic battle environments affected by jamming, interception, signal manipulation, and constantly changing operational conditions. I designed and architected use cases so that every element of workload, identity, and system could continue to operate independently and securely even in degraded or disrupted scenarios. In parallel, I defined the enterprise and solution security architecture with LeanIX, Bizzdesign, and HOPEX as enterprise architecture, repository, and governance platforms to maintain architecture inventory, relationships, traceability, target pictures, and security governance in complex environments. For the architectural designs, I used Sparx Enterprise Architect to describe formal architecture views, interfaces, trust boundaries, and system architecture in both IT and OT environments. IriusRisk was used for threat modeling of the solution to identify architecture-driven risks, derive security requirements, and detect countermeasures and design gaps directly from the solution models. Risk and compliance management was supported with Archer. Architecture decisions, control gaps, and operational risks were translated into controlled governance and auditable compliance measures. For documentation, collaboration, and visual design, I used Confluence to maintain Architecture Decision Records, Security Blueprints, and workflows. I used Lucidchart and draw.io to create design artifacts tailored to stakeholders. I also defined OT security concepts with support from electrical and mechanical engineers in the areas of oil, vehicle onboard systems, rail, power plants, pharma, gas turbines, and nuclear technology. I created the end-to-end OT security strategy, starting with global policy, developed into standards and procedures, and finally aligned with Bell-LaPadula, Purdue Model, SABSA, TOGAF ADM, CENELEC 50701, IEC 62443, and NIST standards. In addition, I worked with engineering team leads to identify critical KBP assets and place them under protective measures that segmented SCADA, PLC, and HMI assets. I drove collaboration between Security, IT, and OT teams to create standardized workflows and use cases for the OT security solution catalog, while integrating Defense-in-Depth and Zero-Trust principles into operational environments. A key part of my work was integrating multidisciplinary engineering, security, and operations stakeholders into a unified security blueprinting strategy and ensuring that architecture, threat modeling, governance, and documentation were technically strong and operationally practical.

• Automation of the database major / minor releases for the TKeasy project

• Concept for database major / minor release automation

• As-is analysis

• Evaluation of Redgate Flyway functionality

• Concept creation

• Products: Redgate Flyway, GitHub, Quest, Erwin Data Modeller, Oracle, Atlassian Jira, Atlassian Confluence

• Skills: Docker, Continuous Delivery, Continuous Integration, Redgate Flyway, Major Releases, Minor Releases

The MiDAS program aims to integrate Generative AI across the entire BBM organization. My role is to enable the eBike division to adopt and leverage Generative AI by collaborating closely with the MiDAS team in India.

Management:

• Enable the eBike division to adopt GenAI through tailored solutions.
• Collaborate with the MiDAS team in India to design solutions for Generative AI use cases specific to the eBike division.
• Coordinate with the eBike teams to integrate GenAI systems, tools, plugins, and services provided by the MiDAS team.
• Plan roadmaps with eBike and MiDAS India team Product Managers for the delivery and integration of Generative AI solutions.

• Interim Teamlead to setup a project with STM32 and NORA Bluetooth module.
• Customer is planning new hardware to replace existing hardware with Bluetooth communication instead cable connection.
• Project was already started but the requirements were not defined.
• System based on STM32 and Nora B106 CPU.
• Analyzing the existing available code base.
• Checking for possible solutions to get the project working.
• Defining the requirements.
• Applying some rules to improve the team communication.
• Working with the NRF tools to get the custom board based on NORA B106 (NRF5340) working.
• Implementation of a simple device communication by Bluetooth.
• Preparation of documentation.
• Leading communication meetings.
• Conducted discussions with customer.
• Tools used: JIRA, OneNote, Git, Confluence, Nordic NRF, Nora B106.

• Further development and maintenance of a complex sales platform with a focus on digital closing processes, customer portal interactions, and document generation for financial and insurance products
• Development and maintenance of microservices with Spring Boot 3 and Kotlin
• Frontend development with Angular 20 for displaying products, applications, and documents
• Execution of end-to-end tests with Playwright and integration tests with WireMock
• Creation and optimization of Quartz jobs and CronJobs
• Refactoring of the security configuration in a multi-realm Keycloak setup with a custom filter chain, permission evaluator, and factory routing
• Creation of dynamic emails with Thymeleaf
• Extensive error analysis with Application Insights, Log Analytics, and direct SQL debugging
• Introduction of a dynamically controlled security architecture with flexible token handling depending on path and realm
• Stabilization and clear structuring of the closing process for complex product models
• Significantly improved maintainability and readability of the code through modular refactorings
• Higher test stability and depth through combined use of Playwright, WireMock, and integration tests
• Targeted performance optimization through analysis of Hibernate statistics, query tuning, and use of SQL execution plans
• Technologies used: Java 21, Kotlin, Spring Boot 3, Angular, TypeScript, REST API, JSON, Kubernetes, Docker, PostgreSQL, Liquibase, Keycloak, OAuth2, GitHub Actions, Testcontainers, Azure Application Insights, Thymeleaf, Tilt, Microsoft SQL Server

• 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

• Industry: Digital music solutions
• Technologies used: Flutter, Dart, iOS, Android, GitLab, PlantUML

• 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

• Bootstrapping a CloudOps team and building a multi-cloud provider backend for a low-code Internal Developer Platform (IDP) with env zero

• Introducing user story mapping, ADRs, milestones, and backlog management

• Designing and developing core APIs, setting up CI/CD pipelines, OpenTofu/Terraform scripts

• Representing and communicating the team with third-party stakeholders (e.g. env zero)

• (Cross-)team coaching on DevOps, software design, Terraform, Golang, and agile practices