Staff Product Security Engineer

Staff Product Security Engineer United States, remote first with NY office available · Full-time · Security · Reports to CISO

About DFNS Finance is moving onchain. Stablecoins, tokenized deposits, securities and funds are changing how money and assets are issued, held and transferred. The destination is a financial system where any asset can be issued, moved and governed onchain with the controls regulated institutions require. That shift needs a new foundation. Just as core banking systems manage accounts and ledgers today, financial institutions need a platform to manage digital assets. DFNS is that platform. Today, we secure hundreds of billions of dollars in assets every month for more than 500 clients worldwide.

Why this role Our platform secures a lot of value. Every code path, dependency and deployment is a potential route to that value. The record we are protecting is zero breaches. You will own the security of the product itself, from threat models and architecture reviews to the secure development lifecycle, pentests, bug bounty and incident response. In year one you will put automated security gates into CI/CD, threat model the signing path and the governance model end to end and become the engineer our clients’ security teams want in the room during due diligence.

What you’ll do

• Own product security across the platform, from threat modeling and design reviews to code review and dynamic testing.

• Build the secure development lifecycle into CI/CD, with SAST and DAST, dependency and supply chain controls (SBOM, signing, provenance) and secrets scanning running as automated gates.

• Lead vulnerability management for the product, from triage and prioritization to fix verification and security releases, with Engineering.

• Run the external pentest program and the bug bounty, and work directly with researchers.

• Lead incident response for product security events, from detection and containment to forensics, post-mortems and the controls that follow.

• Represent our security in client due diligence and audits, from security questionnaires and pentest reports to architecture sessions with bank security teams.

• Raise the bar for every engineer through secure coding guidance, training and reusable security patterns and libraries.

What you bring Must-haves

• Hands-on application security on production systems that handle money or sensitive data, including threat modeling, code review and finding and fixing real vulnerabilities.

• Ability to read and write TypeScript and Rust (or Go) well enough to review and fix security issues yourself.

• Experience building security into CI/CD, including SAST and DAST, dependency and supply chain controls and secrets management.

• Applied cryptography fluency. You know how keys, signatures, TLS and PKI get misused in practice and you can review an MPC or HSM integration without designing the protocol yourself.

• Cloud security on AWS, including IAM, networking and KMS or Nitro Enclaves.

• Experience running pentests or a bug bounty and leading incident response.

• Communication that works with engineers and with external security teams such as bank CISOs and auditors.

Nice-to-haves

• Smart contract security on EVM or Solana.

• Experience with MPC or threshold signature systems, or with HSMs.

• Published research, CVEs or conference talks.

• Experience producing SOC 2 or ISO 27001 evidence for secure development controls.

How we work We are a distributed company headquartered in Paris. Our teams work from Europe, the US and Asia, with offices in New York, Geneva, Dubai, Singapore, Hong Kong and São Paulo. We write decisions down so they survive time zones. We hold our own work to the standards our clients are held to. We hire people who can own an outcome end to end and we give them the room to do it.

What we offer A competitive base salary set by role and location, a bonus or variable plan where the role carries one and stock options vesting over four years. Healthcare, flexible vacation, parental leave and a one-time home technology allowance, with travel expenses covered. A MacBook and the equipment you need to do your best work. Remote first, with an office if you want one.

Base salary range: $150,000-250,000

Hiring process We aim to complete the process in 2 weeks and we tell you where you stand after every step.

• Intro call with Co-CEO (30 minutes).

• Personality and cognitive assessments, completed on your own time (45 minutes).

• A technical take-home exercise

• Focus Interviews (about 3 hours): CISO (30 minutes), technical exercise (45 minutes), general security (45 minutes), design security (45 minutes) and culture fit (30 minutes).

• Reference calls and background checks.

Equal opportunity DFNS is an equal opportunity employer and considers every applicant based on ability and potential, regardless of race, color, religion, sex, gender identity or expression, sexual orientation, national origin, disability, age or any other characteristic protected by law. If you need an accommodation at any point in the process, tell us and we will arrange it.