Paul K.
Lead Flutter Developer
Experience
Mar 2025 - Present
7 monthsLead Flutter Developer
Yourny Travel & Leisure
- Full-stack mobile app development with Flutter and Serverpod for a travel platform – including booking logic, payment integration, real-time features, and DevOps setup.
- Frontend/App Flutter/Dart development – mobile app development with BLoC state management.
- Backend & cloud services – Serverpod integration, Firebase (Auth, Analytics, Remote Config), and real-time communication.
- Mobile platform expertise – deep linking, push notifications, and platform-specific integrations.
- UI/UX & localization – custom design system, animations, localization, OpenStreetMap.
- DevOps & quality – code generation, integration tests, error tracking with Sentry.
- Backend/server Dart & Serverpod – backend development for full-stack applications and real-time features.
- PostgreSQL & external APIs – database management with 3 million hotel records, Google Places, Mollie (payments), and Firebase Authentication.
- Industry knowledge in tourism – hotel booking workflows, multi-user trip planning, payment handling, and accommodation search systems.
- DevOps & cloud – Docker containerization, VPS deployment, environment management, and Sentry monitoring.
- Performance & scalability – database optimization, parallel processing, and large-scale data sync for hotel information.
- Tools: Flutter, Dart, BLoC, Sentry, Firebase (Auth, Analytics, Remote Config, Cloud Messaging), universal links, push notifications, localization, Serverpod, Postgres, Mollie, Docker, VPS deployment, GitHub Actions, GPT, Cursor.
Apr 2024 - Feb 2025
11 monthsSenior Flutter Developer
Elea.ai GmbH
- Development of the first MVP for a lab information system for medical labs.
- Implementation of a barcode scanner using the device camera.
- Implementation of a document scanner using the device camera.
- Close collaboration with company leadership.
- Integrated into a top team with consistently high performance under time pressure.
- Agile workflow following Kanban.
- Tools: Flutter, Dart, BLoC, Intl, Cursor, Firebase, Firestore, GPT.
Dec 2023 - Apr 2024
5 monthsFlutter Lead Developer
St. Leonhards
- Took over an existing prototype.
- Close coordination and planning with project management.
- Integration of Apple's and Google's Health APIs.
- Implementation of the design.
- Connection to the internal API.
- Implementation of animations.
- Agile workflow following Kanban.
- Tools: Flutter, Dart, BLoC, Intl, Visual Studio Code.
Oct 2023 - Nov 2023
2 monthsFlutter Lead Developer
Rewe
- Implementation of the Cookie Planner app.
- Implementation of a local database for recipes, favorites, and ingredients.
- Responsive design for desktop, tablet, and smartphone.
- Implementation of animations with Flutter & Lottie.
- Integration of Rewe SSO via OAuth 2 OpenID Connect.
- Automation of master data conversion from CSV into the data model.
- Agile workflow following Kanban.
- Tools: Flutter, Dart, BLoC, Intl, Hive, Visual Studio Code.
Apr 2022 - Jul 2023
1 year 4 monthsHanover, Germany
Flutter Lead Developer
VetZ GmbH
- Concept, planning, and implementation of an app ecosystem.
- Implementation of the design system in cooperation with the design team.
- Onboarding additional developers and conducting interviews with candidates.
- Mobile app development with Flutter, Dart, BLoC, Intl, and gRPC.
- Prototype development to test various interfaces.
- Agile development following Scrum.
- Tools: Flutter, Dart, BLoC, Freezed, Intl, gRPC, Visual Studio Code.
Dec 2021 - Mar 2022
4 monthsRostock, Germany
Flutter Trainer & Developer
ALTOW Digital Innovation
- Training, onboarding, and coaching the team and new hires in Flutter.
- Designing and implementing an MVP for an internal Flutter app and its architecture.
- Mobile app development with Flutter, Dart, Riverpod, BLoC.
- Prototype development to test various interfaces.
- Agile development following Scrum.
- Tools: Flutter, Dart, Riverpod, Freezed, Visual Studio Code.
Oct 2020 - Mar 2021
6 monthsFrankfurt, Germany
Enhancement of the booking platform
Galeria Reisen
- Frontend development with Angular 12, TypeScript, Sass, Redux, and Docker.
- Backend development with Node.js, Express.js, TypeScript, Swagger, REST, and Docker.
- Using Redis, MySQL, and TypeORM for data storage.
- Agile development following Scrum.
- Onboarding team members.
- First release of the new application.
- Tools: Angular, TypeScript, HTML, SCSS, Redux, Node.js, Express.js, Swagger, REST, Docker, Git, GitLab.
Apr 2020 - Sep 2020
6 monthsFrankfurt, Germany
Development of the automated timetable construction for construction site operations
Deutsche Bahn
- Frontend development with Angular and TypeScript.
- Backend development with Java, Spring Boot, MapStruct, JPA, and Hibernate.
- Coordinating with other teams.
- Training the team in Camunda process control.
- Using MariaDB, AWS, and Protobuf.
- Agile development following Scrum.
- Testing with Cucumber and JUnit.
- Tools: Angular, TypeScript, HTML, SCSS, Node.js, Express.js, Swagger, REST, Docker, Git, GitLab, WebStorm, Cucumber, Camunda.
Oct 2019 - Nov 2021
2 years 2 monthsGiessen, Germany
Lead Developer
DGD Deutscher Gutachter Dienst GmbH
- Tech lead, leading and onboarding new employees.
- Technical design of new features.
- Mobile app development with Flutter, Dart, Redux.
- Backend development with Firebase, Firestore, Cloud Functions, TypeScript, Nest.js, Swagger.
- Agile development following Kanban.
- Deployment management for iOS and Android.
- Conducting usability tests with users.
- Tools: Flutter, Dart, Redux, Firebase, Firestore, TypeScript, Nest.js, Swagger.
Oct 2019 - Dec 2019
3 monthsFrankfurt, Germany
Takeover of a Java legacy application
Picard
- Taking over a Java legacy application for product planning, inventory management, and price calculation.
- Planning the re-implementation.
- Introducing a Scrum development process.
- Onboarding additional developers to the project.
- Developing a concept for re-implementation using future-proof technologies (Java, Spring Boot, Angular).
- Tools: Java, Swing, Angular, TypeScript, HTML, SCSS, Git.
Jan 2019 - Sep 2019
9 monthsFrankfurt, Germany
Implementation of a tourism web application
Thomas Cook
- Frontend development with Angular and Angular Universal (Server-Side Rendering), TypeScript, and Redux.
- Backend development with Node.js, Express.js, TypeScript, Swagger, REST, and Docker.
- Focus on performance.
- Integration of various APIs.
- Agile development following Scrum.
- Tools: Angular, TypeScript, HTML, SCSS, Redux, Node.js, Express.js, Swagger, REST, Docker, Git, GitLab.
Aug 2018 - Dec 2018
5 monthsFrankfurt, Germany
Employee and project management
detim IT Consulting
- Web application for managing projects and employees.
- Frontend development with Angular and TypeScript.
- Backend development with Java, Spring Boot, JPA, Hibernate, and REST.
- Microservice architecture.
- Data storage using MySQL.
- Agile development following Scrum.
- Tools: Java, Spring Boot, JPA, Hibernate, MySQL, REST, Angular, TypeScript, HTML, SCSS, Git, GitLab.
Aug 2017 - Aug 2018
1 year 1 monthHungen, Germany
Development of a desktop application for Vieva
Vitaltec UG
- Development of the Vieva software for the product with the same name.
- Implementation of pulse measurement.
- Hardware communication.
- Visualization of measurement data.
- Porting the core from .NET 4.7 to .NET Standard.
- Development and improvement of data visualization.
- Planning and conducting usability tests.
- Code refactoring.
- Project planning and design.
- Tools: C#, HTML, CSS, JavaScript, Vue.js, Bootstrap, jQuery, Git, GitLab.
Apr 1995 - Present
30 years 6 months(Self-) Development & other projects
Self
- Passion for modern technologies and advanced solutions.
- Ambitious problem solver.
Summary
I help small and medium-sized businesses and startups turn their digital product idea quickly into a market-ready app – without agencies, without detours.
From the idea to the MVP or full-stack product, I guide you pragmatically, structured, and on equal terms – remotely or on-site in Hamburg.
Who I am I'm Paul – a passionate Flutter developer with an entrepreneurial spirit. I know the challenges of startups because I'm building one myself.
That's why I think business-wise in every project:
What brings the most value to the user – not just to the code? How do we get to the goal fast – without building technical debt? My focus is on Flutter and Serverpod – with these I build complete, scalable MVPs and full-stack apps from a single source. I work pragmatically, remotely, and reliably – and always on equal terms.
What I build for you
Flutter App Development Cross-platform apps for iOS, Android, Web & Desktop – with a single codebase, responsive design, and modern architecture. Fast, maintainable, and future-proof.
MVPs & Prototypes Quick-to-build solutions to test ideas – ideal for startups and product teams who want to validate early what really works.
Backend with Serverpod or Firebase Integrated backends with real-time features, authentication, database connection, and payment integration – tailored to your project.
Full control – no vendor lock-in With Serverpod you host your backend yourself: maximum control over data, infrastructure, and costs. No dependency on providers like Firebase or AWS.
API Integration & Platform Services Seamless integration with services like Google APIs, Mollie, OpenStreetMap, OAuth 2, Firebase, or Sentry – stable, secure, and well thought out.
DevOps & Code Quality Clean code, solid architecture, automated tests, GitHub Actions, and Docker-based deployments – for robust apps with a future.
Languages
German
NativeEnglish
AdvancedEducation
Mittelhessen University of Applied Sciences
Bachelor of Science · Computer Science · Giessen, Germany
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