Senior Smart Contract Engineer | Financial Infrastructure & Protocol Development

We're building the $LAKE Crypto Card, a next-generation fintech platform that bridges digital assets with traditional payment infrastructure. Our mission is to make digital assets practical for everyday spending by combining secure smart contracts, transaction processing, wallet infrastructure, settlement systems, and financial-grade backend services into a unified platform. The project is currently in the MVP stage, and we're looking for an experienced Smart Contract Engineer to help design and build the protocol layer that powers secure digital asset operations. What You'll Be Working On You'll collaborate with our engineering team to design and implement secure, scalable smart contracts that integrate with our backend financial infrastructure. Key areas include: - Smart contract architecture and development - Transaction lifecycle management - Authorization, settlement, and reconciliation workflows - Asset custody and wallet interactions - On-chain and off-chain integration - Security and protocol design - Gas optimization and performance - Smart contract testing and auditing - Financial state management Responsibilities - Design and implement production-ready smart contracts using Solidity. - Build secure contract architectures for digital asset transactions. - Develop contract interfaces for backend integration. - Collaborate with backend engineers on transaction workflows. - Review and improve protocol security and efficiency. - Write comprehensive unit and integration tests. - Participate in architecture reviews and technical discussions. - Document contract design and engineering decisions. Required Qualifications - 5+ years of software engineering experience. - 3+ years of Solidity development. - Strong understanding of Ethereum and EVM-compatible networks. - Experience with Hardhat or Foundry. - Experience building and deploying production smart contracts. - Strong understanding of ERC standards (ERC-20, ERC-721, ERC-1155). - Knowledge of smart contract security best practices. - Experience integrating smart contracts with backend services. Preferred Qualifications Experience with one or more of the following is highly desirable: - Payment or settlement systems - DeFi protocols - Multi-signature wallets - Account abstraction - Upgradeable contracts - OpenZeppelin libraries - Chainlink oracles - Cross-chain messaging - Security auditing - Financial or fintech applications