React Experts in Dusseldorf

PLANT-MY-TREE®-per-order

The application enables Shopify merchants to automatically place tree-planting orders for every incoming order. By integrating ecological contributions directly into the purchase process, the manual effort for tracking and billing reforestation initiatives is eliminated. The system increases transparency for end customers through real-time visualizations of the ecological impact directly in the storefront. The architecture is based on a modular monolith with Spring Boot in the backend and an integrated React app inside the Shopify admin area. The solution uses webhooks to capture order data in an event-driven way and integrates the weclapp ERP system for automated monthly invoicing. An app proxy mechanism provides dynamic statistics such as CO2 compensation and planted trees without any performance loss for the merchant shop.

Tasks:

• Design of the modular software architecture based on Spring Modulith to ensure high maintainability
• Development of the event-driven business logic for evaluating Shopify orders via webhooks
• Implementation of automated invoicing by connecting the weclapp REST API
• Building the frontend using React Router and Shopify App Bridge for native integration
• Design of the database model and implementation of the persistence layer with JPA/Hibernate and Prisma
• Integration of internationalization processes for global use in the frontend and email communication
• Automation of deployment processes using Docker and GitLab CI/CD

Project skills: Java 25, Spring Boot, Spring Security, Spring Modulith, Hibernate, JPA, REST API, PostgreSQL, Maven, Liquibase, React, TypeScript, React Router, Vite, Node.js, Prisma, Zod, Docker, Docker Compose, GitLab CI/CD, Shopify CLI, Shopify App Bridge, Polaris, weclapp, i18next, Lombok, Vitest

• In this role, I was responsible as Lead Software Engineer for automating various meat production lines.
• My focus was on developing highly available (High Availability) systems using C/C++.
• I also implemented and supported container orchestration with Kubernetes to ensure smooth and scalable production operations.

• Architected and deployed a live B2B geocoding and demographic-data platform for Germany, combining address lookup with census-based population statistics through a web application and REST API.

• Analysis and remediation of security vulnerabilities in a risk assessment system for energy trading
• System analysis
• Threat modeling
• Decision-making on vulnerability mitigation strategies
• Implementation of vulnerability detection mechanisms
• Security scans
• DevSecOps practices
• Technical environment: Visual Studio Code, JetBrains Suite, MS Threat Modeling Tool, DevSecOps, Git, AWS, DynamoDB, SQL Server, Endur, Snowflake, Orca
• Languages: C#, JavaScript, TypeScript, Python, PowerShell, Bash, Terraform, SQL

• Development of a pilot system to control and monitor multiple GoPro cameras
• Implementation of start, stop, status, media, download, and diagnostic functions via COHN endpoints
• Realization of camera detection, single and group control, as well as stable session/keep-alive logic
• Setup of a download pipeline with queue, retry handling, and temporary files
• Consistent session, folder, and file naming for multi-camera recordings
• Integration of provisioning, certificates, and network operations

• Full focus on AI-augmented web development
• Building and running three proprietary AI-native SaaS products (BrainButler, PageUpgrade, termin365)
• Developing a self-hosted business stack for digital sovereignty
• Daily workflow with Claude as engineering partner and Anthropic/OpenAI APIs for product features
• Using RAG systems with custom vector databases and prompt engineering for complex multi-step pipelines
• Tech stack: Python/FastAPI (backend), React/TypeScript (frontend), WordPress plugin architectures (PHP), multi-tenant systems with per-user encryption

• 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 and implementation of a system to control the entire process for new, removal, and exchange operations of electricity meters by external service providers for a utility company

• Automated retrieval of orders and available devices via defined interfaces (e.g. from SAP)

• Orchestration of process steps (assigning meters, processing meter data, sending updated information back to the source system) using a Spring Boot backend

• Provision of a React-based web client for operational tracking and control of orders, e.g. to continue failed process steps or resend notifications

• Analysis of the possibility of extracting market location data into a separate microservice within an overarching web portal
• Developing a more user-friendly target process based on the current process in coordination with the users
• Coordinating the related architecture concept with architects and developers
• Aligning the related epics and user stories with the relevant departments
• Backlog prioritization and project planning (incl. effort estimation)
• Testing and accepting the implemented user stories
• Technologies/Tools used: MS Office, Jira, Mural, Kotlin, React, GitHub, MS Azure, SQL, Postman, XML, JSON, Kafka, Balsamiq, BPMN

• Led the development of robust, scalable, and high-performance micro-services architecture.
• Migrated legacy monolith systems to Spring Boot with RESTful APIs.
• Designed, implemented, deployed, tested, and optimized scalable backend systems ensuring high availability and performance.
• Maintained and deployed Dockerized applications on Kubernetes integrated into CI/CD pipelines.
• Collaborated with cross-functional teams, including frontend developers, product managers, and designers, to translate business requirements into scalable and efficient backend solutions.
• Mentored team members and contributed meaningful code reviews.

• Supported an agile team in the development of a new CRM tool
• Web frontend development (Angular 17 with MDB-Bootstrap, microfrontends, DDD)
• Backend development (C# & .NET 7-9, MongoDB, MassTransit, RabbitMQ, Elasticsearch, microservices, DDD)
• Coordination with stakeholders & product owners
• Assisted in sprint planning

• Development of an interactive prototype for the concept of an AI-supported Enterprise Architecture Management tool. The goal was to present complex relationships between IT systems, business processes, and departments in a way that is easy to understand and to support decision-making in the context of IT transformations.

• The prototype combined data-driven analyses with guided questions and interactive visualizations. A central part was the integration of a RAG process to provide domain-specific EAM knowledge in context. The focus was on quick idea validation, user-centered interaction design, and the technical feasibility of a scalable overall concept.

• Design, implementation, and validation of a RAG process for domain-specific EAM knowledge with Python, LangChain, and graph/vector databases (Neo4J, Milvus)

• Business and technical requirements analysis as well as definition of an MVP

• Development of the architecture and technology concept using Angular, Spring Boot, GraphQL, and Kubernetes

• Design of an interaction concept and creation of a brand style guide with Figma

• Development of interactive prototypes with Angular, Konva.js, and TypeScript

• Integration of CI/CD processes with GitLab CI/CD