Mobile Developers in Germany

• Planned and developed a CPU monitoring application for monitoring system performance and resource utilization.
• Designed and implemented a Spring Boot backend providing a REST API for processing and exposing monitoring data.
• Developed the React frontend for presenting monitoring information in a clear and user-friendly interface.
• Integrated PostgreSQL for persistent storage and management of application data.
• Containerized the application and its services using Docker Compose.
• Automated infrastructure provisioning and deployment using Terraform on AWS.
• Structured the application as a modern, maintainable system using REST-based communication between frontend and backend.
• Designed and developed a secure, scalable CPU monitoring architecture (cpu-watcher) with a dedicated collector application that streams monitoring data to the backend, reducing direct exposure of system resources.
• Designed a secure cloud infrastructure with the database isolated within a private network and OIDC-based authentication.
• Implemented Infrastructure as Code with Terraform and integrated version-controlled CI/CD pipelines to automate testing, infrastructure changes, and application deployments.
• Designed and implemented the frontend delivery architecture using AWS CloudFront.

Stack: Spring Boot · React · PostgreSQL · REST API · Docker Compose · Terraform · AWS

Participation in the EU-funded MORANE-2 project to validate the Future Railway Mobile Communication System (FRMCS) in real-world use cases: preparation of the requirements specifications for TOBA and the associated test specifications.

Technologies: 5GS (Radio & Core), FRMCS, MCx (MCPTT, MCData, MCVideo), MC Gateway UE, MCx Priority/Security/QoS Management, ETCS, SIP, IMS

Gronic Ident & Sign

Core technologies: Android, Jetpack Compose, Retrofit, Regula Document Reader, Adobe Sign

Android app on dedicated devices for identifications and electronic signatures at the PoS

• Developing a model-based AI where natural language is interpreted as formal relations.
• Natural language terms are not considered rigid but fluid and can be negotiated in a context so meaning resolves by iteratively specifying.
• Develops all kinds of model solutions.
• Backed by natural language and data annotation.
• Requirements to code and other solutions.

• Developed a Flutter app for eID ID card logins
• Focus: Flutter, iOS, eID, AusweisAppSDK, Mason, Keycloak, Agentic Coding, Arc42, Jenkins

struppilog.com – Digital health record for pets / MVP → Full Product

Design, development, and full further development of a digital health platform for pets – from my own MVP development to a fully built and production-ready platform.

Independent concept and development of the MVP Development of the full application with Flutter/Dart and Firebase Expansion of the MVP into a full digital health record with health data, findings, allergies, medications, documents, and emergency data Development of user registration, authentication, roles, data models, and secure user interactions Implementation of QR-code-based data exchange and digital interaction features Development of a multilingual, responsive web application Integration of AI-supported features and AI/agentic workflows Development and continuous improvement of product logic, UX/UI, and technical architecture Building and expanding a scalable cloud-based solution with Firebase Integration and further development of APIs and external services Use of AI-native / agentic engineering to speed up development, testing, debugging, and product iteration Independent implementation of all other features and technical extensions Continuous further development of the MVP into a full digital product

Impact: The MVP I built myself was continuously developed technically and functionally into a broad, production-ready platform – including frontend, backend, data model, authentication, UX/UI, APIs, cloud infrastructure, and ongoing product development.

Responsible for the strategic and operational coordination of app development for Landkreis Hameln-Pyrmont

• Development and implementation of the digitalization strategy for citizen-oriented mobile services and the optimization of internal administrative processes
• Requirements engineering: systematic capture of complex administrative requirements and conversion into structured user stories
• Stakeholder management: coordination between departments, citizens, administrative levels, and external service providers within multi-level committee structures
• Prioritization and management of the Product Backlog, taking compliance requirements and regulatory specifications into account
• Participation in agile ceremonies and coordination meetings for continuous product improvement
• Integration of GDPR requirements and administration-specific security standards into the development process
• Citizen participation: coordination of feedback processes and user-oriented tests to increase digital citizen satisfaction

• RLHF & Model Evaluation: Evaluated, ranked, and refined Large Language Model (LLM) responses based on accuracy, reasoning quality, safety guidelines, and factual correctness.
• Data Annotation & Prompt Engineering: Created high-complexity prompts, edge-case scenarios, and gold-standard reference answers to train and fine-tune generative AI models.
• Quality Assurance & Verification: Conducted rigorous fact-checking, logical consistency validation, and multi-turn response optimization.

• Independently carried out integration, testing, and acceptance activities on 5G core systems in a containerized test environment; structured test protocols and documentation
• Built a 5G core and RAN integration environment from scratch (Docker Compose) for reproducible test scenarios across multiple vendor configurations
• Performed fault analysis and troubleshooting across the entire protocol stack (SBI, RRC, NAS, NGAP, TLS) to precisely isolate integration issues
• Contributed to the BSI-related NESAS-CCS-GI evaluation project – experience in security-critical, regulated customer projects

• Contributed to the architecture design process, leading to scalable and maintainable solutions for complex projects
• Improved app performance through code optimization and implementation of efficient algorithms
• Led a team of iOS developers to complete projects on time and achieve customer satisfaction
• Implemented core design plans into complete iOS app frameworks and delegated project components to corresponding team members
• Key project: City Guide ([link]

• Development of an iOS app that combines public transport and sharing services
• Collaboration in Scrum within a large cross-functional team
• Creation of reusable components with SwiftUI and Combine
• Development of custom solutions for Apple Maps

Conceptualizing and developing AI-powered app MVPs from the first idea to a working product. I combine UX strategy with modern AI and no-code tools — especially Claude and Claude Code, where I work directly in the terminal on real code (React, Vite), complemented by Figma, Bolt.new, and Base44 — to quickly validate and build product ideas. Personal platforms: Nutrycoach.ai (AI nutrition coaching with role-based dashboards for clients, coaches, and admins, AI meal analysis, and a scalable design system) and LuxuryBandit (content/creator app). This led to my own practice 'AI-assisted App Strategy', which combines human creativity, UX logic, and intelligent automation.

• Support in restructuring and designing the group's internal Android apps
• Defining essential modules and implementing accessible components
• Establishing agile approaches at an international level
• Technologies & Methods: Kotlin, Android, JUnit 5, Koin, Azure DevOps, Android Studio, Git, Jetpack Compose, Coil, Flow API, Ktor, Coroutines, TypeScript, Node.js

• Further development of the Android app "StarMoney"
• Major XML to Compose redesigns
• Introduction of new technologies and architecture
• Implementation of instant bank transfer
• Development following the agile Scrum process