Senior Application Security Engineer

Gemini•New York, NY

8h•Hybrid

About The Position

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. The Application Security (AppSec) team exists to make sure security is never an afterthought. We are on a mission to secure products at the time of thought and the time of build: at the product requirements doc, the technical architectural decision, at the line of code. We believe that security input is most valuable before the work is done and after-the-fact is too late and too expensive. As a Senior Application Security Engineer on the Application Security team, you will be a trusted partner to engineering, product, and business teams across Gemini. You will help guide teams to design and build secure products while building systems and culture that embed security judgment into every team. Gemini is AI-first and AppSec builds the tools to make this vision secure.

Requirements

5+ years of experience in application security or similar roles
Ability to perform design reviews, threat modeling, secure code reviews, or penetration testing with an attacker mindset
Experience building or meaningfully contributing to security tooling and automation
Strong background in application security best practices and familiarity with common vulnerabilities (e.g. SSRF, race conditions, privilege escalations, etc.)
Some background in development or scripting experience (Python, Scala, C++, or JavaScript) with the ability to read and write code
Strong communication skills to influence without authority and the ability to collaborate on a cross-functional team with competing priorities

Nice To Haves

Experience building AI application security tooling using agents or skills
Experience with supply chain security, common frameworks (SLSA, OWASP SPVS) and other CI/CD security controls
Familiarity with highly regulated environments (financial services, fintech, crypto, or equivalent) and ability to understand business objectives, business context, and security risk
Experience with preventing application security vulnerabilities at scale through secure design patterns, automated tooling, or frameworks
Experience with microservice architectures and cloud-native environments

Responsibilities

Lead secure design reviews, threat modeling, code review, and penetration testing for high-risk products such as crypto custody, trading systems, and payments
Build and ship code: design and build AppSec tooling including AI agents for secure design and code review, AI-enhanced SAST/DAST pipelines, and automation that eliminates repeatable security toil
Partner with engineering teams to remediate vulnerabilities and drive long-term improvements in secure coding practices