About Karsten
German
Native or bilingual
English
Fluent
Experience
- Doctos GmbHLead Software Developer + CTOMay 2023 - Today (3 years and 2 months)München, Germany
Full-Stack & Backend Development
- Developed backend systems with Python/FastAPI and C#/.NET for a healthcare SaaS product used by dental practices
- Built REST APIs, data models, integrations, and workflows for documentation, billing, and practice-management features
- Worked hands-on across backend, frontend, mobile, infrastructure, and automation
IT Infrastructure & Architecture
- Planned and led a modern IT infrastructure, including database design, API structures, integrations, deployments, and operations
- Designed and maintained complex PostgreSQL database structures
- Led the migration from a self-hosted setup to a Kubernetes production environment on STACKIT
- Worked with Docker deployments, CI/CD workflows, and production processes
Speech Recognition & AI
- Integrated Azure Speech Service into a voice-based documentation and billing application for dental practices
- Implemented pre- and post-processing of audio data to improve transcription quality
- Reduced speech recognition error rates to below 5%
- Built AI-driven workflows that transform spoken input into structured documentation and billing output
App & Web Development
- Developed a modular Flutter application with native packages for iOS using Swift and Windows using C++
- Built and maintained internal CMS functionality and admin tools with Angular
- Contributed to features across mobile, web, backend, and API layers
Robotic Process Automation
- Enhanced a C#-based RPA application for automating Windows applications and manual workflows
- Improved automation logic, reliability, and maintainability
Technical Leadership
- Shaped the technical roadmap, software architecture, and development priorities
- Organized development processes using Scrum and Kanban
- Recruited, onboarded, and mentored developers
- Provided code reviews, technical guidance, and performance feedback
- Managed priorities, timelines, and delivery in a fast-moving startup environment
- marpinion GmbH + minnt GmbHSoftware DeveloperFebruary 2018 - July 2022 (4 years and 5 months)München, Germany
- Developed and maintained hybrid apps with Xamarin for medical professionals (physicians, pharmacists)
- Built WCF Web Services and backend logic
- Created and maintained an Angular-based CMS
- Modernized IT infrastructure by migrating to Microsoft Azure (DevOps)
- teamsports.aiLead Software DeveloperAugust 2022 - April 2023 (9 months)Berlin, Germany
- Continued development of a sports-focused Flutter app, introducing new features and optimizing performance
- Refactored a native Android/iOS "Family and Groups Organizer" app to Flutter
- Established a new developer mobile team, defining processes for continuous development cycles and ensuring streamlined collaboration
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Education
- Bachelor's Degree in Business Informatics,University of Applied Sciences2017Bachelor's Degree in Business Informatics,
- Software Engineering studies,Heilbronn University2009Software Engineering studies,