Freelancer Senior Mobile Engineer (React Native, Expo, TypeScript) m/w/d
easybill GmbH2 days ago
Berlin, 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.
- Develop the app architecture, navigation, reusable components, forms, and data-access structures.
- Integrate and extend API functionality, including typed interfaces, validation, caching, loading states, and error handling.
- Implement secure authentication, session management, and careful handling of sensitive customer and business data.
- Address mobile performance, platform-specific behavior, connectivity changes, accessibility, and multilingual support.
- Create automated tests and verify behavior on simulators and physical devices.
- Help shape build, release, monitoring, and app-store publication processes.
- Contribute to features from ideation through release and subsequent improvement, using AI tools such as Claude Code while maintaining output quality and correctness.
Requirements
- Freelance status and senior-level experience with TypeScript, React Native, and Expo.
- Experience taking mobile applications beyond implementation through release.
- Strong understanding of React, component architecture, state management, and asynchronous data flows.
- Knowledge of iOS and Android platform differences, 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 independently extend interfaces.
- Experience with automated testing, maintainable code, and clearly documented technical decisions.
- Independent, pragmatic working style with clear communication and customer-focused judgment.
- Fluent German and good English skills.
- PHP and Symfony knowledge is preferred; EAS, Swift or Kotlin native modules, app-store publication, mobile release processes, published apps, open-source contributions, and GitHub experiments are additional advantages.
Benefits
- Remote-first work with no location requirement.
- Flexible, trust-based working environment with substantial autonomy.
- Opportunity to contribute to company strategy and culture.
- Engaged 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.