Senior Backend Developer (Web3)

TL;DR

Senior Backend Developer (Node.js/Web3): Developing DeFi yield products and gasless transaction services for a blockchain hardware wallet ecosystem with an accent on EVM transaction models, meta-transactions, and secure on-chain interactions. Focus on building scalable backend layers for signing and monitoring transactions, integrating new yield protocols, and ensuring high operational discipline for fund-managing services.

Location: Remote (Global)

Company

A high-tech blockchain company providing secure smartcard-based hardware wallets and mobile applications for digital asset management.

What you will do

• Develop and maintain DeFi yield and gasless transaction services on the on-chain product surface.
• Add support for new blockchain chains, fee tokens, and yield protocols.
• Build backend layers to sign, broadcast, and monitor on-chain transactions.
• Implement meta-transaction flows using standards like EIP-712 and EIP-7702.
• Own production releases, including migrations, rollback plans, and RPC failover.
• Write unit, integration, and E2E tests while ensuring service observability.

Requirements

• Strong production experience with Node.js and NestJS.
• Hands-on experience building on EVM chains with ethers.js or viem.
• Deep familiarity with the EVM transaction model, including signing, gas, and nonces.
• Proficiency in PostgreSQL and writing efficient SQL queries.
• Solid understanding of common application security vulnerabilities.
• Experience with monitoring, logging, and debugging production issues.

Nice to have

• Background in DeFi infrastructure.
• Familiarity with modern transaction standards like EIP-7702, ERC-2771, or ERC-4337.
• Experience with distributed locking and concurrency primitives.

Culture & Benefits

• Remote work from anywhere in the world.
• Competitive salary paid in EURO or USDT.
• 20 working days of paid vacation per year.
• Compensation for necessary technical equipment.
• Paid sick leave and birthday presents.