Staff Security Engineer, Product & Platform

Job Title: Staff Security Engineer, Product & PlatformLocation: Seattle, WA****Full-Time Role****The RoleAs the client’s first dedicated security engineer, you’ll join as a Staff Security Engineer, Product & Platform and own product and platform security end to end, shaping how we design, build and operate secure agentic systems as we scale.This is a deeply hands-on Staff IC role where you’ll set the technical direction for security, build the systems and controls that matter most and partner closely with engineering as our platform and customer base grow. You’ll work alongside our IT and compliance lead, who owns GRC and corporate IT, and have significant autonomy to determine where security investment will have the greatest impact.What You’ll OwnDefine and drive client’s product and platform security strategy, prioritizing investments against the risks that matter most as we scale.Lead threat modeling for our agentic platform and design protections across agent behavior, permissions, isolation, customer data and platform boundaries.Harden our application and cloud infrastructure across production access, IAM, secrets management and the CI/CD supply chain.Partner with engineering to build secure-by-default patterns into how agents, services and infrastructure are designed and shipped.Own security detection and incident response for the platform, including logging standards, detection coverage and response processes.Represent technical security in enterprise customer reviews and architecture discussions, translating our approach clearly to customer security teams.Own the technical controls that support SOC 2 in partnership with our IT and compliance lead, ensuring controls are effective in practice as our systems evolve.Help shape the future of security, including identifying where we need additional capabilities and helping hire future security team members.What We Need8+ years of experience in security engineering, including Principal or Staff-level ownership across complex production systems.Deep product security experience across threat modeling, secure architecture, authentication and authorization and multi-tenant systems.Strong hands-on experience with cloud security, Kubernetes, IAM and infrastructure as code.A strong technical point of view on securing LLM and agent-based systems, with the ability to reason about emerging risks from first principles.Experience leading security incident response for production services and improving systems based on what you learn.A track record of writing and shipping production code, security tooling or infrastructure, not just reviewing the work of others.Strong judgment and comfort making pragmatic security tradeoffs in fast-moving environments without an established playbook.Clear communication with engineers, company leadership and enterprise customer security teams.Nice to HaveExperience as an early security hire at a high-growth B2B SaaS, AI or infrastructure company.Experience building security detections, telemetry and logging pipelines in cloud environments.Experience implementing technical controls for SOC 2 or ISO 27001, or contributing to AI security research, standards or open-source security tooling.Applicant Notices & DisclaimersFor information on benefits, equal opportunity employment, and location-specific applicant notices, click here