Senior Security Engineer

A high-growth AI-native platform is hiring a Security Engineer as their second security hire to own security across cloud infrastructure, application surfaces and their AI agent stack.

This is a hands-on IC role with real scope. You'll build and scale the security programme from the ground up rather than maintain something that already exists, working closely with product and infrastructure engineering to embed security into how the business ships. Expect to own entire security domains end to end and shape how the company approaches an emerging area few teams have solved yet: securing AI agents in production.

Role: Security Engineer

Salary: $200,000 - $315,000

Location: Hybrid, San Francisco

What you'll be doing:

• Own security reviews and threat modelling for new and existing product surfaces across the AI-native platform
• Build and improve core security processes including secure SDLC and detection and response
• Harden cloud and application infrastructure and drive remediation of high-priority risks
• Help define how the business secures AI agents and governs their use, including guardrails, data exposure, prompt-injection and abuse risks
• Support enterprise customer trust through compliance (SOC 2) and customer-facing security needs
• Partner closely with product and infrastructure engineering to embed security into shipping cycles

What you'll need:

• 3 to 8 years hands-on information security experience, with core work in security engineering rather than shipping product features or GRC-only work
• Dedicated Security Engineer background with a primary domain in infrastructure and cloud security (GCP preferred, AWS or Azure also fine)
• Track record building security systems end to end: detection and response, secure SDLC and infrastructure hardening, not just strategy or process documentation
• Prior experience at an early-stage or high-growth startup (sub-500 headcount) where you built or scaled security infrastructure from scratch
• High-slope career trajectory with clear scope and title growth
• Ambitious, hands-on builder who thrives in ambiguity and is excited to own entire security domains as the second hire
• Strategic communicator able to articulate problems and approach at an executive level, not only in technical detail

Nice to have:

• Experience securing agentic AI or LLM systems, including guardrails, data exposure or prompt injection
• Enterprise compliance experience (SOC 2, ISO 27001)

This role would suit a hands-on Security Engineer who wants to own entire domains, sit close to the founders and shape how a fast-moving AI-native business approaches security, including the parts nobody has fully figured out yet.