Matthias Pfeifer
Windermere
Summary
Experienced Software Engineer specializing in Java and microservices architecture. Developed scalable applications and enhanced code reliability while mentoring teams and implementing agile methodologies. Focused on delivering high-quality solutions in fast-paced environments.
Overview
8
8
years of professional experience
Work History
Independent Contractor – AI Reasoning & Model Evaluation
Mercor.io
02.2026 - Current
- Evaluated complex decision paths, enhancing model logic and reliability.
- Analyzed and annotated reasoning trajectories, improving performance of large language models.
- Applied software engineering reasoning methods, supporting AI model training and evaluation.
Frontend Developer
hosting.de
03.2025 - 07.2025
- Developed modern UI components with Angular, TypeScript, and Tailwind CSS to enhance user experience.
- Integrated frontend services with REST APIs and JSON backend systems to streamline data flow.
- Modernized legacy components and supported containerized deployments with CI/CD pipelines.
- Mentored junior developers, fostering skills and contributing to elevated frontend architecture standards.
Senior Java Developer
DEKRA
05.2022 - 12.2024
- Designed scalable backend services aligned with enterprise architecture strategies.
- Developed enterprise-grade Java applications to enhance performance in high-demand client environments.
- Established development standards that increased code reliability and maintainability across projects.
- Collaborated with cross-functional teams to ensure delivery of stable, scalable production systems aligned with business needs.
Senior Application Developer
Nuance Communications
01.2018 - 03.2022
- Developed Java backend services for IVR platforms and conversational AI systems, enhancing user interaction.
- Provided production support and optimized performance for global enterprise clients, ensuring system reliability.
- Built internal configuration tools for Nuance Mix enterprise deployments, streamlining configuration processes.
- Participated across the full SDLC including architecture, development, testing, and deployment.
Education
Master of Science - Computer Science
RWTH-Aachen Universtity
Germany05-2008
Skills
- REST APIs
- Microservices Architecture
- Java
- Spring Framework
- Angular
- TypeScript
- JavaScript
- SQL
- Docker
- Kubernetes
- CI/CD
- Bamboo
- Git
- Oracle Database
- JSON APIs
- Agile
- SDLC
Remote Opportunities
True
Selected Project Experience
- Enterprise REST API Platform – Java / Spring, Designed scalable backend services supporting enterprise integrations and API communication., Implemented JSON data exchange and database integration., Containerized services using Docker for flexible deployment.
- Angular Customer Portal, Developed responsive UI components using Angular and TypeScript., Integrated REST APIs enabling real-time application functionality.
- Containerized Microservices Deployment, Designed container-based architecture using Docker., Implemented CI/CD pipelines supporting automated builds and deployments.
Timeline
Independent Contractor – AI Reasoning & Model Evaluation
Mercor.io
02.2026 - Current
Frontend Developer
hosting.de
03.2025 - 07.2025
Senior Java Developer
DEKRA
05.2022 - 12.2024
Senior Application Developer
Nuance Communications
01.2018 - 03.2022
Master of Science - Computer Science
RWTH-Aachen Universtity