Matthias B.-Senior Software Developer and Software Architect
Check rate
Experience
Architecture and development of a modern, AI-powered corporate website
Matthias Baumann Software Development
Design, architecture and development of a modern, AI-powered corporate website, including full-stack implementation and an integrated RAG-based chatbot for context-sensitive user interactions. The frontend uses Next.js 16 (App Router) with React 19, TypeScript and Tailwind CSS 4. PayloadCMS 3 serves as a headless CMS with multilingual support (DE/EN) via MongoDB and next-intl. Lexical handles rich-text editing. The chat interface uses React Markdown with streaming for real-time AI responses. The RAG service runs on Python/FastAPI with Haystack 2. Requests are vectorized via an OpenAI-compatible embedding API (intfloat-multilingual-e5-large) and stored in Qdrant. Retrieval results are passed to a self-hosted LLM (LocalAI) for context-aware responses. Rate limiting and session management use MongoDB. A Quarkus 3 microservice (Java 25) serves as a web crawler, extracting text via jsoup and indexing it in Qdrant. It is compiled as a GraalVM Native Image for minimal resource consumption. A separate bot probe service (also a Quarkus/Java 25 Native Image) monitors bot availability by simulating 19 different bots (Googlebot, Bingbot, social media crawlers, etc.) and detecting blocks caused by WAF rules, CAPTCHAs or HTTP errors. An integrated React dashboard visualizes the results in real time. The infrastructure runs on a self-hosted K3s cluster. BunkerWeb serves as a reverse proxy with WAF and automated ACME certificate management. Plausible Analytics provides privacy-compliant tracking. CI/CD via GitLab CI automates builds, Docker images, Helm deployments and smoke tests, with feature branches deployed to separate staging environments. Claude Code (Anthropic) was extensively used for architecture planning, code generation, reviews, debugging and infrastructure configuration, significantly speeding up development. Quality assurance includes Vitest (unit tests), Playwright (E2E tests), Testcontainers for database integration and ClamAV for antivirus scanning of uploads.
Senior Software Developer
HARTING Technology Group
- Played a key role in the technical redesign and migration of a large B2B platform from a legacy commerce system to a modern, containerized microservices architecture on Azure
- End-to-end design and implementation of the extended Contentful Headless CMS ecosystem
- Led the development of a custom application based on the Contentful App Framework (React, Forma36) to manage the content translation workflow
- Integrated the Across Translation Management System into Contentful (XLIFF via FTP, SOAP)
- Integrated Canto’s Media Delivery Cloud for digital asset management
- Full-stack development with TypeScript, React and Node.js
- Ensured high quality through pair programming, pair reviews and automated tests (Jest, Playwright, Storybook)
- Continuous deployment with Azure DevOps in an agile/Scrum environment
Senior Software Developer and Software Architect
Market leader in components, systems and solutions in the electrical engineering sector from North Rhine-Westphalia
- Transformed an on-premises monolith into a cloud-native Self-Contained Systems (SCS) architecture
- Contributed to the full lifecycle of a company-specific content management platform based on Contentful (design, setup, international rollouts, stabilization)
- Requirements analysis in close collaboration with editorial stakeholders
- Used agile methods (Scrum, later Kanban)
- Deployed microservices/SCS as Docker containers in the AWS cloud
- Used Server-Side Includes (SSI) to integrate ERP/PIM content
- Developed Contentful Extensions and Apps for translation (Across), asset management (Canto), SEO management and editorial workflows
- Asynchronous system communication via Kafka and synchronous REST interfaces
- Delivered the frontend via nginx as a reverse proxy
- Quality assurance through pair programming, pair reviews and automated tests (JUnit, Cucumber, Selenium, Testcontainers)
- Continuous deployment via GitLab pipelines
Senior Software Developer and Software Architect
Leading provider of ID documents
- Integrated a Manufacturing Execution System (MES) into an expanded production environment for custom card production
- Extended the SOAP-based interface and documented and coordinated with machine manufacturers and PLC programmers
- Extended an existing test application to support machine test engineers
Senior Software Developer and Software Architect
Freelance
- Designed and implemented an IoT solution based on Raspberry Pi and ESP32
- Controlled and interacted with sensors and actuators
- Assembled the system software
Senior Software Developer
Leading electrical engineering components, systems and solutions provider from North Rhine-Westphalia
- Extended the backend in an existing SOA environment
- Set up a build system with Maven and Jenkins
- Developed a new application based on JEE (EJB 3.1, REST WebServices), Spring MVC and Portlet 2.0
Senior Software Developer
RIS (Rewe Informations Systeme GmbH)
- Connected a mobile data capture device to a backend system
- Designed and established a build and dependency infrastructure with Maven and Quickbuild
- Implemented business logic in a three-tier architecture (REST web service, EJB/business layer, database)
Senior Software Developer
Leading provider of ID documents
- Designed and implemented a JEE application in a SOA environment
- Integrated a workflow engine to control printing machines
- Developed a test application with a GUI (Java Swing) for machine test engineers
- Implemented a simulator with integrated monitoring via a web application
Software Developer
Leading provider of ID documents
- Migrated an enterprise application from BEA WebLogic 9.3 to IBM WebSphere 6.1
- Migrated and extended an SWT-based client application
Software Developer
Automotive group
- Migrated an application based on Documentum 5.3 to Documentum 6.0 and 6.5
- Introduced test automation with JMeter
- Analyzed requirements, designed and implemented a SOAP-based web service interface for the DMS
Software Developer
Webware-Experts OHG
- Design and implementation of an XSD-to-XSD mapping tool (xsd2xsd) based on XUL
- Development of the graphical user interface with XML User Interface Language (Mozilla) and JavaScript
Software Developer
Webware-Experts OHG for automotive group
- Further development of a Cocoon-based web application for the B2B platform of an automotive group
- Development of server applications based on J2EE in a SOA environment
- Design and implementation of a Lucene search engine with JCA connectors
- Configuration interface for search engine integration
- Communication through firewalls between host and legacy systems
Software Developer
Wolfsburg
- Architectural redesign of a monolithic B2B platform (Java/DAO) using the MVC pattern
- Design and implementation of an XML interface for the existing Java object model
Software Developer
Compumedia GmbH
- Development of order management software in MS-Access for commercial and logistics processes
- Support for orders, inventory management, finance, and invoicing
- C implementation to control and connect wireless handheld scanners to a database
Freelance Software Developer
Geoforschungsinstitut Potsdam
- Development of GIS generalization algorithms and prototyping
- Specification and implementation of algorithms
- Design and implementation of a test application to validate the results
Industry experience
See where this freelancer has spent most of their professional time.
Experienced in Information Technology, Manufacturing, Automotive, Professional Services, Government and Administration, and Retail.
Business area experience
See which departments and functions this freelancer has contributed to most.
Experienced in Information Technology, Product Development, Quality Assurance, Finance, Logistics, and Production.
Summary
I am a seasoned software architect and developer with broad experience in designing and implementing modern, cloud-native architectures, containerized microservices and headless CMS solutions. I excel in full-stack development with a focus on Java , Spring Boot, TypeScript, React and Node.js, ensuring reliable quality through proven testing and agile methodologies.
I deliver value by transforming legacy systems into scalable, efficient platforms, integrating diverse technologies from ERP to IoT, and fostering maintainability. I have a solid background in digital asset management, multilingual content workflows, and real-time data processing across industries.
Skills
- Java
- Spring Boot
- Kafka
- Contentful
- Node
- React
- Azure Devops
- Typescript
- Docker
- Application Architecture
- Uml
- Mongodb
- Postgresql
- Javascript
- Css
- Aws
- Cucumber
- Selenium
- Gitlab
- Jenkins
- Arc42
- Documentdb
- Devops
Languages
Education
AWT Berlin
Communications Technician · Berlin, Germany
Certifications & licenses
Brightest and Pearson VUE
Ibm Business Process Manager Advanced
IBM
OOSE Hamburg
Statistics
Experience
Expertise
Qualifications
Frequently asked questions
Have questions? Find more information here.
Matthias is based in Petershagen, Germany and can operate in on-site, hybrid, and remote work models.
Matthias speaks the following languages: German (Native), English (Advanced).
Matthias has at least 29 years of experience. During this time, Matthias has worked in at least 5 different roles and for 13 different companies. The average length of individual experience is 2 years. Note that Matthias may not have shared all experience and actually has more experience.
Based on recent experience, Matthias would be well-suited for roles such as: Architecture and development of a modern, AI-powered corporate website, Senior Software Developer, Senior Software Developer and Software Architect.
Matthias's most recent position is Architecture and development of a modern, AI-powered corporate website at Matthias Baumann Software Development.
In recent years, Matthias has worked for Matthias Baumann Software Development, HARTING Technology Group, Market leader in components, systems and solutions in the electrical engineering sector from North Rhine-Westphalia, and Freelance.
Matthias is most experienced in industries like Information Technology, Manufacturing, and Automotive. Matthias also has some experience in Professional Services, Government and Administration, and Retail.
Matthias is most experienced in business areas like Information Technology, Product Development, and Quality Assurance. Matthias also has some experience in Finance, Logistics, and Production.
Matthias has recently worked in industries like Information Technology and Manufacturing.
Matthias has recently worked in business areas like Information Technology, Product Development, and Quality Assurance.
Matthias attended AWT Berlin.
Matthias has 3 certificates. These include: Isaqb® Certified Professional For Software Architecture, Ibm Business Process Manager Advanced, and Omg Certified Uml Professional.
Matthias is immediately available full-time for suitable projects.
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Calculated based on our freelancers’ daily rates as of 12 Nov 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
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