Senior Smart Contract Engineer

Role Description

We are looking for a Smart Contract Engineer to design, implement, test, and maintain production-grade smart contracts across multiple blockchain ecosystems. This role focuses primarily on EVM-based Solidity contracts and Solana programs written in Rust using the Anchor framework, while also building the backend services that power and integrate with those contracts. As a Smart Contracts Engineer, you’ll be responsible for building secure and efficient smart contracts that power Circle’s core protocols.

• Design and implement production-grade smart contracts across EVM and/or Solana ecosystems using Solidity and Rust
• Develop backend services and integration layers that interface with deployed smart contracts and internal systems
• Research and apply industry-standard design patterns and emerging best practices in smart contract and distributed systems engineering
• Optimize smart contract performance, including gas efficiency, while enforcing strong security through secure architecture and defensive coding practices
• Build and maintain transaction orchestration flows, event listeners, and indexing services that bridge on-chain and off-chain components
• Test, deploy, and manage upgrades for smart contracts and backend services in production environments
• Partner with security teams on audits, threat modeling, remediation, and production monitoring to ensure reliability and operational excellence

Qualifications

• Proven experience designing and developing production-grade smart contracts in Solidity and/or Rust, with strong emphasis on security, gas optimization, and performance
• Deep understanding of blockchain architecture, EIP standards, decentralized systems, and on-chain execution models
• Strong knowledge of smart contract security principles and common vulnerability patterns (e.g., reentrancy, access control flaws, arithmetic errors)
• Experience with smart contract development and testing frameworks such as Foundry, Hardhat, or Anchor
• Working knowledge of backend development, particularly services that interact with blockchain networks (transaction submission, event processing, indexing)
• Experience integrating smart contracts with backend systems and off-chain infrastructure
• Experience designing and deploying production-grade, scalable cloud services in AWS, Google Cloud, Microsoft Azure, or similar environments
• Strong collaboration skills with the ability to work cross-functionally with product, infrastructure, and security teams

Requirements

• Experience shipping or operating multi-chain or cross-chain smart contract systems, with familiarity in Web3 fintech or DeFi environments
• Experience contributing to or auditing open-source smart contracts or blockchain protocols
• Experience developing smart contracts for non-EVM chains

Benefits

Circle is on a mission to create an inclusive financial future, with transparency at our core. We consider a wide variety of elements when crafting our compensation ranges and total compensation packages. Starting pay is determined by various factors, including but not limited to: relevant experience, skill set, qualifications, and other business and organizational needs. Please note that compensation ranges may differ for candidates in other locations.

Company Description

We are an equal opportunity employer. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status, or any other protected status required by the laws in the locations where we hire. Additionally, Circle participates in the E-Verify Program in certain locations, as required by law.

Should you require accommodations or assistance in our interview process because of a disability, please reach out to View email address on us.fitly.work for support. We respect your privacy and will connect with you separately from our interview process to accommodate your needs.