Senior Security Engineer

Founding Security Engineer | AI Security | San Francisco (on-site)

I'm retained with a seriously well-funded AI security company, build by a team fresh out of frontier labs and working with the very same labs now and across fortune 500s.

They're looking for their first security hire - full remit and a bar set right at the top of the market.

Day to day, you’ll be:

• Taking solid AWS foundations and making them exceptional, hands-on in Terraform and IAM
• Reviewing new features with engineering before they ship
• Writing the security policies and building out incident response
• Owning company-wide security, from how documents get shared to the network itself
• Handling enterprise customers’ security reviews with the sales team
• Setting the security roadmap, then shipping it yourself

Once the the firm is secure you'll have opportunities to move onto different areas whilst still maintaining core security: adversarial testing of AI agents, prompt injection, poisoned MCP servers, agents attacking other agents. You'll be expected to use your judgement and breadth of experience to continue adding to their security posture, they're a bright team and this role will pay a big part in their growth. I promise you won't be left twiddling your thumbs here.

What you’ll need:

• An engineering background. You write real code as well as policy
• Years of hands-on security engineering, and the seniority to set direction with no team behind you
• AWS and Terraform inside out (deep GCP is fine if you’re happy to transition)
• Start-up experience. You’ve owned broad scope somewhere small and fixed things yourself rather than raising tickets
• A feel for what enterprise security teams want to see when they vet a vendor
• Ideally, an attacker’s mindset (CTFs, bug bounties, vuln research) and a real interest in how AI agents get broken

This position is office based. You sit next to the founders, advise a range of CISOs and get feedback in minutes.

What’s on offer:

• Base + significant equity, pitched at the top end of the market
• Health, dental and vision for you and your dependents
• Lunch and dinner every day
• Visa sponsorship and relocation support if you’re not in SF yet

If you’re the engineer other security engineers call when the proverbial hits and fan and have a genuine interest threat and vulnerability, message me or apply below.