Full-Stack Engineer (Web3-DeFi) à France

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Full-Stack Engineer (Web3-DeFi) based in France. This fully remote opportunity is ideal for a full-stack engineer passionate about blockchain technology and decentralized finance. You’ll take ownership of core product features from day one, working closely with the founding team. The role combines frontend and backend development to create seamless, consumer-grade DeFi experiences. You’ll integrate with protocols, DEX aggregators, cross-chain bridges, and crypto APIs across multiple blockchain ecosystems. As part of a fast-moving startup, you’ll have significant autonomy and influence over technical decisions and product direction. Your work will help shape an all-in-one DeFi platform designed to make decentralized finance more accessible and intuitive. The environment rewards initiative, technical excellence, curiosity, and rapid execution. Accountabilities: - Lead full-stack development and deliver product features from conception through implementation. - Architect and build integrations with DeFi protocols, DEX aggregators, cross-chain bridges, and data providers. - Develop polished, responsive, and performant user interfaces using Next. js, React, and TailwindCSS. - Design, implement, and maintain scalable backend services using Node. js, TypeScript, PostgreSQL, Redis, and WebSockets. - Proactively identify technical challenges, propose solutions, and independently drive execution. - Collaborate directly with the founding team to define technical direction, architecture, and product strategy. - Contribute to product quality, security, performance, and continuous improvement.

Requirements: - 3–5+ years of hands-on experience in crypto or Web3 development, including DEXs, wallets, aggregators, or DeFi protocols; alternatively, demonstrate exceptional technical aptitude and strong proof of capability. - Strong proficiency in Next. js, React, and TailwindCSS for building high-quality user interfaces. - Solid backend development experience with Node. js and TypeScript, including PostgreSQL and the ability to write clean, secure, and scalable code. - Proven experience integrating crypto APIs, DeFi protocols, and third-party aggregators. - Excellent communication skills and the ability to explain technical concepts clearly while collaborating in a remote environment. - A startup mindset, with strong self-direction, comfort navigating ambiguity, and a focus on delivering results quickly. - High intellectual curiosity, analytical thinking, and a passion for solving complex problems and improving continuously. - Nice to have: Experience with account abstraction, including ERC-7702 smart wallets. - Nice to have: Deep understanding of DEX and AMM mechanics, cross-chain bridges, and liquidity management. Benefits: - Fully remote work environment, with the opportunity to work from anywhere. - Ownership and responsibility over core product features from day one. - Direct and measurable impact on how users interact with the platform. - Fast-paced, high-performance environment focused on execution and results. - Potential pathway to technical leadership as the organization grows. - Opportunity to contribute to innovative products at the forefront of DeFi. - Close collaboration with the founding team and influence over product and technical direction.