Senior Fullstack Developer (NestJS & React)

🏷️Title: Senior Fullstack Developer (NestJS + React)

👫Department: Engineering

📍Location: UK or Europe, Remote

About Block Labs

Block Labs is a leading force in the Web3 space, incubating, investing in, and accelerating top-tier fintech, crypto and iGaming projects. With a mission to shape the future of decentralized technology, we partner with visionary startups to raise funding, refine product-market fit, and grow their audiences. Our diverse team drives innovation, using deep industry expertise and an extensive network to empower the next wave of blockchain-driven companies. At Block Labs, we’re passionate about turning bold ideas into breakthrough success.

About The Role

As a Senior Fullstack Engineer, you will design and develop scalable, high-performance applications that integrate blockchain technologies. You'll work across both frontend and backend, collaborating closely with engineering and product teams to build end-to-end Web3 experiences. Your focus will be on creating secure, seamless, and performant applications that interact with smart contracts, wallets, and decentralized protocols.

Key Responsibilities

• Develop and maintain backend services using NestJS (Node.js, TypeScript).
• Build responsive, high-performance user interfaces using React and TypeScript.
• Design and implement secure, scalable APIs for Web3 applications.
• Implement wallet interactions, on-chain transactions, and real-time updates in the frontend.
• Implement third-party integrations for on-ramps, swaps, and other blockchain services.
• Optimize database queries, caching strategies, and frontend rendering for performance and scalability.
• Build and maintain event-driven architectures for blockchain transaction processing.
• Implement authentication and authorization mechanisms, including Web3 identity solutions.
• Ensure security best practices across the stack, including encryption, access control, and smart contract interactions.
• Collaborate with product, design, and engineering teams to ship high-impact features.
• Write clean, maintainable, and testable code while contributing to documentation and code reviews.
• Help shape internal standards and developer experience in a fast-moving Web3 environment.
  
  

About You

• 4+ years of backend development experience with Node.js and TypeScript.
• 2+ years working with NestJS or similar frameworks.
• Experience designing and maintaining APIs optimized for mobile applications.
• Strong understanding of blockchain fundamentals and experience integrating with EVM-compatible chains.
• Experience with DevOps tools and cloud providers.
• Knowledge of authentication best practices and Web3 identity solutions.
• Strong problem-solving skills and ability to work autonomously in a remote-first environment.
• Experience with Fireblocks or similar MPC-based custody platforms is a plus.