Senior Software Security Engineer

Fieldguide is hiring a Senior Software Security Engineer to help build its security function and make secure practices easier for its engineers. The role spans secure design, identity and secrets management, cloud security, and security for AI agents, while partnering with Product and Platform teams.

Responsibilities:

• Partnering with engineering to find the biggest risks in a system before it ships, and building secure frameworks and libraries that make control adoption the path of least resistance
• Building and maintaining identity and secrets management systems, including credential issuance, rotation, and workload authentication. We’re moving towards short-lived, workload-based identity across our cloud and Kubernetes environments
• Hardening our cloud security controls and contributing to continuous cloud security posture management through infrastructure-as-code scanning, misconfiguration detection, and automated remediation
• Building the security model for AI agents that perform audit work. You’ll design permission boundaries that enforce what agents can see and do, harden them against prompt injection in untrusted documents, and ensure strict tenant isolation across our agentic platform
• Raising the security bar across engineering through design reviews and coaching, helping teams build securely without a gate in the way

Requirements:

• You have 5+ years of software engineering experience building and maintaining security-relevant systems in production
• You've led a security initiative from design through adoption, and you can point to engineers who are safer and faster because of it
• You have hands-on experience with identity and secrets management, including protocols such as OAuth 2.0 and OIDC
• You're familiar with Kubernetes security primitives, including RBAC, namespaces, network policies, and admission controllers
• You reason clearly about trust boundaries and threat models to prioritize risk
• You thrive on breadth, ambiguity, and evolving priorities rather than a single narrow lane
• Experience with developer security tooling such as SAST, dependency scanning, or secure build infrastructure
• Experience with SAML or SPIFFE/SPIRE, or building workload authentication systems from scratch
• Experience securing LLM-based or agentic systems