The client is an innovative global fintech leader behind USDT, the world’s largest and most widely used stablecoin.
We are looking for a React Native Developer with solid experience in blockchain/crypto/ wallets to help us build secure applications. Responsibilities * Development Design, develop and maintain secure cross-platform mobile applications for iOS and Android using React Native (Expo). Work closely with designers to ensure the UI is clean, fast and accessible. Write clean, testable, and well-documented code, following best practices. * Integration Integrate JavaScript SDKs, crypto wallet libraries, backend services and low-level native modules into mobile applications Work with Bitcoin / Web3 / blockchain APIs and wallet backends. Implement and manage wallet functionality: addresses, balances, transactions, seed phrases, private keys (with secure handling only). * Collaboration Work closely with backend, product and design teams to deliver innovative crypto wallet and DeFi features. Participate in architecture discussions, code reviews and technical decision-making. * Security & Reliability Implement mobile security best practices: secure storage, encryption, device integrity checks, protection from common attack vectors. Contribute to performance optimization, monitoring and reliability of mobile apps used at global scale.
Requirements * * Deep experience with React and React Native (Expo) * Strong knowledge of JavaScript and ES6+, and familiarity with modern front-end tooling. * Experience with Redux and related React ecosystem fundamentals. * Proven background in crypto or wallet development (Bitcoin, Web3, wallets, private keys or similar technologies). * Understanding of decentralized systems and concepts like public/private keys, signing, transactions, and fees. * Strong experience integrating REST APIs and WebSockets; real-time data handling. * Experience with native modules (e.g. in C++) and low-level integrations. * Hands-on experience in Swift or Objective-C (iOS) or Kotlin or Java (Android) for low-level mobile integrations. * Familiarity with CI/CD pipelines for mobile deployments. * Good understanding of mobile security: secure storage, key management, encryption, secure communication. * Comfortable working in a remote, distributed team, communicating in English (written and spoken).
Nice to Have * Experience with hardware wallets or secure elements. * Knowledge of Layer 2 solutions, sidechains, or Lightning Network. * Background in cryptography or security engineering. * Experience with performance optimization and profiling for mobile apps
