Senior Solidity Engineer

About the Client

A fast-growing fintech innovator is building decentralized lending infrastructure for real-world use cases. The company powers cross-border payments and tokenized custody through smart contracts that connect institutional liquidity with borrowers globally. By combining programmable vaults, permissioned flows, and investor protections, the team is bridging crypto capital with TradFi applications.

Backed by major industry players, the company is expanding rapidly across Latin America and Southeast Asia, offering scalable liquidity, FX management, and real-time settlement solutions via blockchain.

Role Overview

The Senior Solidity Engineer will take a lead role in developing and optimizing the smart contracts that form the foundation of the protocol’s lending and payments infrastructure. This includes working on ERC-4626 vaults, wallet integrations, and smart contract flows designed to manage liquidity, credit, and investor activity securely and efficiently.

Key Responsibilities:

• Design, build, and audit smart contracts for DeFi lending, vault management, and payment scheduling.

• Implement secure design patterns, including modular architecture, upgradeability, access control, and automation.

• Develop smart contract flows for borrower onboarding, investor interactions, and multisig wallet support.

• Integrate smart contracts with front-end apps, backend APIs, and cross-chain bridges.

• Lead internal code reviews and collaborate with external auditors to ensure protocol security.

• Optimize gas usage and mitigate risks related to MEV, reentrancy, and contract exploits.

• Work cross-functionally with product and engineering teams to deliver core features.

Requirements:

• 4+ years of experience writing and deploying Solidity smart contracts.

• Deep understanding of DeFi lending mechanics, ERC standards (ERC20, ERC4626), and vault structures.

• Proven experience with wallet integrations (e.g., Gnosis Safe) and custody providers (e.g., Fireblocks).

• Proficiency with development tools such as Foundry or Hardhat, TypeScript, and GitHub workflows.

• Experience deploying to mainnet and maintaining smart contract systems.

• Security-focused mindset with a strong understanding of auditing processes and mitigation strategies.

Preferred Qualifications:

• Familiarity with zk-proof integrations, EAS attestations, or permissioned lending frameworks.

• Experience with cross-chain protocols and integrations (e.g., Aave, Morpho, Compound).

• Contributions to public DeFi or open-source projects.

• Understanding of on-chain credit scoring or credit logic simulation.