Web3 Protocol Engineer: Cross-Chain & Smart Contracts

Fun; San Francisco (CA); On-site; USD 180,000 - 260,000; Full time

Job summary

Fun is building the infrastructure powering Web3 payments and decentralized finance. We are seeking a Protocol Engineer to join our core blockchain team and shape secure, scalable on-chain primitives and cross-chain integrations.

You will design and implement production-grade smart contracts, collaborate with backend and product engineers, and participate in security reviews and audits to ensure protocol safety. The role offers fast-paced impact in fintech infrastructure.

Qualifications

• Production smart contracts on major blockchain platforms.
• Strong understanding of DeFi primitives and token standards.
• Ability to explain complex blockchain concepts to non-technical stakeholders.

Responsibilities

• Design, implement, and deploy secure smart contracts and protocol components.
• Collaborate with backend and product teams to meet requirements.
• Participate in security audits and formal verification efforts.
• Research new blockchain technologies and integration opportunities.
• Troubleshoot and debug on-chain issues to ensure protocol reliability.

Skills

Blockchain protocol knowledge

Security auditing mindset

Cross-chain concepts

Communication with cross-functional团队

Tools

Solidity

Rust

Move

Job description

Fun is building the infrastructure powering Web3 payments and decentralized finance. We are seeking a Protocol Engineer to join our core blockchain team and shape secure, scalable on-chain primitives and cross-chain integrations.

You will design and implement production-grade smart contracts, collaborate with backend and product engineers, and participate in security reviews and audits to ensure protocol safety. The role offers fast-paced impact in fintech infrastructure.