Freelancer Senior Mobile Engineer (React Native, Expo, TypeScript) m/w/d
easybill GmbH12 days ago
Willich, GermanySenior
Responsibilities
- Develop and evolve the easybill-mobile application for iOS and Android with React Native, Expo, and TypeScript.
- Translate invoicing and document requirements into clear mobile workflows and high-quality native interfaces.
- Extend the mobile architecture with maintainable navigation, reusable components, forms, and data-access structures.
- Integrate and manage API data, including typed interfaces, validation, caching, loading states, and error handling.
- Extend the PHP and Symfony REST API when needed to support mobile functionality.
- Implement secure authentication, session management, and careful handling of sensitive customer and business data.
- Address mobile performance, platform-specific behavior, changing network conditions, app switching, and device differences.
- Ensure accessibility and multilingual support as part of product quality.
- Write automated tests and validate behavior on simulators and real devices.
- Help shape build, release, monitoring, and app-store publication processes.
- Challenge requirements, propose solutions, and support features from concept through release and ongoing improvement.
- Use AI tools such as Claude Code while remaining accountable for the quality, clarity, and correctness of the resulting code.
Requirements
- Freelance senior-level experience with TypeScript, React Native, and Expo, including taking mobile applications through release.
- Strong understanding of React, component architecture, state management, and asynchronous data flows.
- Knowledge of iOS and Android platform characteristics, performance troubleshooting, platform issues, and debugging.
- Experience integrating APIs and understanding API contracts, authentication, validation, and error handling.
- Ability to understand existing API endpoints, diagnose app-backend issues, and extend interfaces independently.
- Experience with automated testing, maintainable code, and clear technical decision-making.
- Independent, pragmatic working style with clear communication and customer-focused judgment.
- Fluent German and good English skills.
- PHP and Symfony experience is preferred.
- Experience with EAS, native Swift or Kotlin modules, app-store publication, mobile release processes, published apps, open-source contributions, or public GitHub experiments is advantageous.
Benefits
- Remote-first work with no location requirement.
- Flexible, trust-based working environment with substantial autonomy.
- Opportunity to influence company strategy and culture.
- Collaborative team working on innovative solutions.
- Regular team events.
Tech Stack
Categories
Mobile
About easybill GmbH
easybill GmbH builds SaaS invoicing and finance-automation software for freelancers, SMBs, and e-commerce merchants, including e-invoices compliant with GoBD and over 60 marketplace and shop integrations. Its products include easybill for billing and easybill Connect for syncing orders, shipping, and tax data across e-commerce systems; more than 27,000 companies use the service. Founded in 2007 and headquartered in Kaarst, Germany, easybill is part of Paqato.