Senior Blockchain Security Engineer

Gemini; San Francisco, New York (CA, NY); Hybrid; USD 140,000 - 200,000; Full time

Job summary

A leading crypto and Web3 platform in San Francisco is seeking a Senior Blockchain Security Engineer to lead security reviews and collaborate with on-chain engineering teams on security best practices. Ideal candidates will have over 5 years of experience in application and Web3 security, a strong background in smart contract audits, and excellent communication skills. This role offers a competitive salary and a hybrid work environment.

Benefits

Competitive starting salary

Annual bonus

Equity grant

Comprehensive health plans

401K with company matching

Paid Parental Leave

Flexible time off

Qualifications

• 5+ years of experience in application security, Web3 security, or similar roles.
• Ability to perform design reviews and threat modeling.
• Experience with secure key management and wallet systems.

Responsibilities

• Lead security reviews of smart contracts and Web3 applications.
• Collaborate on-chain engineering teams on security best practices.
• Develop and improve security tooling for blockchain ecosystems.

Skills

Application security

Web3 security

Smart contract audits

Secure coding practices

Blockchain security tools

Communication skills

Tools

Slither

Echidna

Job description

About the Company

Gemini is a global crypto and Web3 platform founded by Cameron and Tyler Winklevoss in 2014, offering a wide range of simple, reliable, and secure crypto products and services to individuals and institutions in over 70 countries. Our mission is to unlock the next era of financial, creative, and personal freedom by providing trusted access to the decentralized future. We envision a world where crypto reshapes the global financial system, internet, and money to create greater choice, independence, and opportunity for all — bridging traditional finance with the emerging cryptoeconomy in a way that is more open, fair, and secure. As a publicly traded company, Gemini is poised to accelerate this vision with greater scale, reach, and impact.

Department: Application Security

Role: Senior Blockchain Security Engineer

As a member of the Application Security (AppSec) team, you will share in the responsibility of protecting the company and our customers against application security threats. The AppSec team is focused on the advancement of modern application security practices and supports the engineering organization by finding, fixing, and preventing software security vulnerabilities.

As a Senior Blockchain Security Engineer on the Application Security team focusing on blockchain security, you will work closely with on-chain engineering and product teams to provide security recommendations and identify security issues throughout the on-chain software development lifecycle. You will lead security reviews of Web3 products, integrate secure development practices into our on-chain SDLC, and develop tooling to identify, mitigate, and monitor blockchain-specific threats.

This role is required to be in person twice a week at either our San Francisco, CA or New York City, NY office.

Responsibilities

• Lead in-depth security reviews of smart contracts, blockchain protocols, and Web3 applications for architectural flaws, security vulnerabilities, and best practice violations
• Collaborate and advise on-chain engineering teams on Web3 security best practices and vulnerability remediation
• Design and implement secure on-chain SDLC processes for on-chain product teams
• Develop, maintain, and improve security tooling for blockchain ecosystems (fuzzers, static analysis, etc.)
• Partner with legal, compliance, and risk teams to address security, regulatory, and operational risks of blockchain features

Minimum Qualifications

• 5+ years of experience in application security, Web3 security, or similar roles
• Strong background in Web3 security reviews such as smart contract audits, blockchain protocols, and dApps
• Ability to perform design reviews, threat modeling, secure code reviews, or penetration testing with an attacker mindset
• Strong background in application security best practices and familiarity with common vulnerabilities (e.g. SSRF, race conditions, privilege escalations, etc.)
• Experience with secure key management and wallet systems
• Familiarity with blockchain security tools (slither, echidna, etc)
• Some background in development or scripting experience (Python, Scala, C++, JavaScript, etc.)
• Familiarity with and ability to understand business objectives, business context, and security risk
• Strong communication skills and the ability to collaborate on a cross‑functional team

Preferred Qualifications

• Experience with formal verification of smart contracts
• Prior experience in cryptocurrency exchanges, DeFi platforms, or NFT marketplaces
• Active contributor to blockchain security communities, bug bounty programs, or published exploit researchAbility to define and execute a long‑term blockchain security roadmap in partnership with engineering leadership

It Pays to Work Here

Competitive starting salary

Benefits

• Competitive starting salary
• A discretionary annual bonus
• Long‑term incentive in the form of a new hire equity grant
• Comprehensive health plans
• 401K with company matching
• Paid Parental Leave
• Flexible time off

Salary Range

The base salary range for this role is between $140,000 - $200,000 in the State of New York, the State of California and the State of Washington. This range is not inclusive of our discretionary bonus or equity package. When determining a candidate’s compensation, we consider a number of factors including skillset, experience, job scope, and current market data.

In the United States, we offer a hybrid work approach at our hub offices, balancing the benefits of in-person collaboration with the flexibility of remote work. Expectations may vary by location and role, so candidates are encouraged to connect with their recruiter to learn more about the specific policy for the role. Employees who do not live near one of our hubs are part of our remote workforce.

At Gemini, we strive to build diverse teams that reflect the people we want to empower through our products, and we are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, or Veteran status. Equal Opportunity is the Law, and Gemini is proud to be an equal opportunity workplace. If you have a specific need that requires accommodation, please let a member of the People Team know.