Freelancer profile translated to English.
Back to original languageAbout Karsten
I am a full-stack developer and lead developer with extensive experience in the conception and implementation of complex IT solutions. My focus is on cross-platform apps (especially with Flutter), stable backend architectures, and performant database structures. For example, I successfully migrated a Xamarin app with over 30,000 active users to Flutter, coordinating a team of experts and restructuring the entire IT infrastructure.
In my role as CTO, I also planned and implemented a completely new database architecture and backend solutions for a health-tech startup, which led to significant performance and stability gains. The further development of a modular app architecture to flexibly adapt the system to new requirements also fell within my area of responsibility.
I am particularly passionate about innovative ideas in start-ups, for which I offer a holistic solution for their digital product landscape – from planning and development through deployment to scaling. It is important to me to contribute both technical expertise and structured working methods and to help teams work efficiently and solution-oriented.
German
Native or bilingual
English
Fluent
Can work on-site
Heilbronn (up to 50km)
Experience
- Doctos GmbHLead Software Developer + CTOMay 2023 - Today (3 years and 1 month)München, Germany
IT Infrastructure & Architecture
- Planned and implemented a brand-new IT infrastructure, covering database design, integrations, and UI development
- Designed and maintained complex database structures using PostgreSQL
Speech Recognition & AI
- Integrated Azure Speech Service for a voice-based documentation and billing application for dental practices
- Performed pre- and post-processing of audio data, reducing error rates to below 5%
App Development
- Developed a modular Flutter application with native packages (Swift for iOS, C++ for Windows)
- Built and maintained an internal CMS using Angular
- Enhanced a Robotic Process Automation (RPA) application in C#
- # Leadership & Strategic Direction
- Shaped the company's technology strategy and roadmap
- Spearheaded the recruitment, onboarding, and training of new developers
- Organized sprints and daily stand-ups using Scrum and Kanban to ensure efficient workflow, clear accountability, and timely delivery
- Provided in-depth code reviews, performance feedback, and career development support, while managing resource allocation and project timelines
- 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
Recommendations
Be the first to recommend Karsten
Help this freelancer shine by sharing your experience working together.
These freelancer profiles also match your criteria
Agatha Frydrych
Backend Java Software Engineer
4.7
(3)
2
Baptiste Duhen
Fullstack developer
4.6
(4)
5
Amed Hamou
Senior Lead Developer
4
(2)
7
Audrey Champion
Web developer
4.3
(3)
4
Education
- Bachelor's Degree in Business Informatics,University of Applied Sciences2017Bachelor's Degree in Business Informatics,
- Software Engineering studies,Heilbronn University2009Software Engineering studies,