Protocol Engineer

fun.xyz • New York, NY

23h

About The Position

Fun builds infrastructure for consumer-facing fintech applications, including onboarding, account access, and money movement, to help users interact with blockchain-based systems. The Protocol Engineer will join the core blockchain team to build Web3 payments infrastructure and work on technical challenges involving smart contracts, cross-chain protocols, and decentralized finance. The role focuses on designing and implementing secure, efficient smart contract systems and blockchain integrations across multiple chains.

Requirements

• Strong experience building and deploying production smart contracts on major blockchain platforms.
• Deep understanding of blockchain architecture, consensus mechanisms, and cryptographic principles.
• Hands-on experience with smart contract development languages such as Solidity, Rust, or Move.
• Solid grasp of DeFi protocols, token standards, and cross-chain communication patterns.
• Strong security mindset and knowledge of common smart contract vulnerabilities and best practices.
• Clear communication skills, including the ability to explain complex blockchain concepts to cross-functional teams.

Nice To Haves

• Production experience with multiple blockchain ecosystems, such as Ethereum, Solana, and L2s.
• Previous experience at a crypto startup or Web3 infrastructure company.
• Experience with cross-chain bridges, oracles, or interoperability protocols.
• Background with high-volume DeFi protocols or DEX infrastructure.
• Contributions to blockchain open-source projects or protocol research.
• Experience with formal verification or advanced smart contract testing frameworks.

Responsibilities

• Design, develop, and deploy secure smart contracts and protocol implementations across multiple blockchain platforms.
• Collaborate with backend and product teams to architect blockchain solutions that meet business requirements.
• Write efficient, well-tested code and participate in security audits to ensure protocol safety.
• Research and evaluate blockchain technologies, protocols, and DeFi primitives for integration opportunities.
• Contribute to incident response and debugging of on-chain issues to ensure protocol reliability.

What This Job Offers

• Job Type: Full-time
• Education Level: No Education Listed