JavaScript Experts in Cologne

Software engineering and integration consulting for enterprise clients, with a focus on backend development, APIs, system integration, and event-driven architectures. Currently developing and evolving a recruitment and staffing platform using Elixir and RabbitMQ, including asynchronous, event-driven communication and integrations with external recruitment and staffing platforms.

• Structured analysis and evaluation of business processes

• Gathering, documenting, and prioritizing requirements

• Creating business-friendly and technically executable process models

• Use of Camunda tools

• Deriving requirements and interfaces from BPMN diagrams

• Coordination with stakeholders and business units

• Translating business requirements into technical solution designs

• Implementing efficient and tailored applications

• Systematic collection, analysis, and documentation of requirements

• Prioritizing and validating requirements in close collaboration with stakeholders

• Alignment between business and development to ensure shared objectives

• Creating use cases, user stories, and acceptance criteria

• Continuous requirements and change management throughout the project lifecycle

• Define project goals and create project plans

• Delegate tasks and monitor project progress

• Monitor budgets and inform stakeholders

• Mendix: Architecture, development, and maintenance of custom applications (Microflows, Domain Model, Security, XPath)

• Modeling Mendix workflows for process optimization

• Develop scalable apps with Mendix including REST/SOAP integration with SAP, SQL, Azure & SharePoint

• UI design for Mendix using Atlas UI, Fluent UI, HTML, CSS, JavaScript

• Develop web & mobile apps with Mendix using agile methods (Scrum, Kanban)

• Implement business logic with Mendix Microflows and Nanoflows

• Performance optimization and architecture improvements for Mendix applications

• Conduct Mendix training

• Create technical documentation and best practices for Mendix

• Coaching and mentoring for low-code development with Mendix

• Self-hosted table tennis equipment platform.
• Development of a custom “Racket Builder” that uses a co-evolutionary genetic algorithm to identify, evaluate, and recommend the optimal combinations of racket blades and rubbers based on physics heuristics and player data within a search space of over 4 billion combinations.
• Development of a custom fully automated web crawler to capture equipment specifications, integrating an automated pipeline for image normalization as well as data harmonization via DeepSeek.
• Cloudflare Edge Workers written in Rust to perform low-latency data searches and offload computationally intensive simulations from the main server.
• High performance and accessibility standards across a large Nuxt 4 codebase achieving 95–100/100/100 Lighthouse scores.

• SPA for automated communication of medical findings with role-based access (Sanctum)
• Server-side LLM integration (OpenRouter) with structured processing
• Automated sending via SMS/voice call (Twilio, ElevenLabs) with queue + status retry
• Full test coverage with 80+ documented test cases

Technologies: PHP, Laravel, LLM API (OpenRouter), Twilio, ElevenLabs, Laravel Sanctum, PHPUnit, Playwright, Docker, REST

• 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.

• Led the end-to-end architecture and migration of a legacy on- premise IoT monitoring system to a cloud-native Azure platform within a 17-member development team
• Designed and implemented a scalable microservices architecture (Java 21, Spring Boot, Kubernetes, Azure Services), decoupling IoT data streams and eliminating legacy system bottlenecks
• Defined technology stack, mentored developers, and orchestrated cross-functional teams in 4 countries to ensure high-quality delivery and alignment with architectural standards
• Drove requirements engineering and system redesign, removing years of technical debt and introducing event-driven processing and automated workflows
• Key Achievements
• Increased system stability and uptime by ~10x, eliminating need for 24/7 DevOps intervention
• Reduced hosting costs by ~80% (5x savings) through cloud optimization
• Improved performance and scalability, enabling stable handling of high-volume IoT data streams
• Delivered successful zero-disruption migration from on-prem to cloud, with strong user satisfaction and reliability from day one

Technologies: Java 25, Selenium, Insomnia, SSO, Gitlab, Jenkins, Docker, Kubernetes, Jira, IntelliJ, Nexus, Oracle, MariaDB, SpringBoot, Grafana, Concept Board, Vue.js, OpenApi, Kotlin. Implementation, maintenance, and enhancement of automated end-to-end regression tests for UI and API interfaces. Appropriate and targeted test automation involving multiple software products, including Java-based Windows applications. Automation of business processes with Selenium, reset jobs, and DB import jobs, as well as creation of test concepts, test case descriptions, and structured defect reporting.

• Created an application to control measurement hardware with a Tauri application using React.JS and TypeScript on Raspberry Pi
• Developed a cloud application for storing and analyzing measurement results using Spring Boot and React.JS
• Built a Tauri application for printing ZPL labels on Windows
• Technologies: Java, JavaScript, Tauri, Rust, React.JS, AWS, Kubernetes, Docker, GitLab CI/CD, REST API (JSON), Maven, CI/CD, PostgreSQL

• Building an AI-native coaching platform for cyclists: a conversational Dynamic Coach that turns training and recovery data into the next session decision, available daily instead of a static calendar.

• Designed and shipped a full-stack, chat-first coaching experience on Next.js and the Vercel Edge Network, with agentic workflows that adapt plans in real time to readiness, load, and life constraints.

• Built integrations with Garmin, Strava, Whoop, and intervals.icu so sleep, HRV, and ride data feed coaching recommendations without manual data entry.

• Product thesis: make high-quality coaching principles accessible at scale by combining adaptive training logic with plain-language conversation, not another metrics dashboard.

Industry: digital sovereignty, public sector

Responsibilities:

• Project coordination (teams: consulting, development, testing, deployment/operations)

Products and standards:

• Jira, Confluence, Asana, Miro, Mural
• Open Source, Keycloak, Open Xchange, ownCloud

• AI-assisted creation of test cases and test data
• Creation of test cases based on requirements
• Execution of manual tests
• Defect documentation, retesting and tracking

Technologies & Tools: SCRUM, Jira, Confluence, Zephyr Scale

Project: Digitalization of Warehouse Processes | Building a Data Analytics Platform.

• Built a web-based workforce allocation system that digitized daily shift planning by matching worker expertise to operational zones, replacing manual coordination with a structured workflow adopted across the site, saving supervisors time on daily planning.
• Developed a real-time operational visibility dashboard giving supervisors a live view of task throughput and outstanding workload across warehouse zones throughout the day, helping reduce overtime and idle labour costs.
• Developed a slotting optimization solution to improve warehouse picking efficiency and reduce picking time per order, working directly with operations teams from concept through production deployment.

Technologies used: Python, Django, PostgreSQL, Pandas, NumPy, HTML, Java, JavaScript, Docker, Kubernetes, AWS, Power BI, GitHub Actions CI/CD, GitOps, Claude, OpenAI

• Built more than 15 frontend applications and more than 10 backend services across internal tools, back-office workflows, and external portals for installers and end customers
• Automate build and release workflows with TypeScript and Azure DevOps
• Mentor junior engineers through code reviews and technical guidance
• Integrate AI-assisted and agentic development practices into engineering workflows
• Coordinate user experience decisions with UX designers

Tech Stack: Claude Code, Codex, AWS (S3, Lambda, AppSync, Resolver), Next.js App Router, ReactJS, NuxtJS, Vue.js, Storybook, JavaScript, TypeScript, GraphQL, Azure DevOps

• Backend WordPress web development.