React Native Developer (Blockchain/Crypto)

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