Principal Software Engineer — Application Security & AI Trust Architecture

In this Principal Software Engineering role at Cisco Systems, you will help set the security direction for software platforms and services, with a specific focus on application security and AI trust architecture. The work spans from defining security architecture and threat modeling to turning high-level strategy into secure-by-default, spec-driven engineering practices across cloud-to-box products.

This onsite position is based in San Jose, CA. The salary range for this role is USD 220,900 - 380,000 per year, and the position requires 15+ years of experience.

What you will do

• Define and drive security architecture across software platforms and services.
• Translate security strategy into hands-on engineering execution, ensuring products are secure from the cloud to the box.
• Lead cross-functional initiatives and mentor engineering team members.
• Engage with customers and leverage AI to improve the development lifecycle and threat prevention capabilities.
• Collaborate with application teams to design secure-by-default software patterns.
• Implement strict Model Context Protocol (MCP) access boundaries.
• Enforce spec-driven security contracts across application interfaces.
• Mitigate vulnerabilities unique to autonomous agent workflows, including prompt injection, indirect data exfiltration, and unauthorized tool invocation.
• Design trust boundaries, sandboxing models, and execution guardrails for autonomous application agents and LLM tool-calling workflows.
• Architect granular authentication, authorization, and least-privilege scoping for MCP servers, tool registries, and external integrations.
• Mitigate emerging AI threat vectors such as OWASP Top 10 for LLMs, indirect prompt injection, tool hijacking, credential harvesting, and context leakage.
• Establish spec-driven security standards across application contracts including OpenAPI, TypeSpec, and gRPC/Protobuf, embedding authentication schemes, data sanitization, and authorization scopes directly into machine-readable specs.
• Implement automated security contract testing and static/dynamic schema validation to detect authorization bypasses, Broken Object Level Authorization (BOLA), and injection vulnerabilities before deployment.
• Lead comprehensive architectural threat modeling for critical application tiers, distributed business logic, and multi-tenant data boundaries.
• Create reusable, hardened software design patterns, cryptographic utilities, and session management frameworks for application engineering teams.
• Architect and scale automated security gates in CI/CD pipelines including SAST, DAST, IAST, software composition analysis, container image signing, and SBOM tracking.
• Define policy-as-code frameworks (for example, OPA/Rego and Cedar) to enforce deterministic security baselines across service deployments.
• Act as the principal technical escalation point for complex application security architecture reviews and critical vulnerability disclosures.
• Mentor senior engineers on defensive coding practices, modern API security standards, and zero-trust application design.

Requirements

• Bachelor’s degree in Computer Science, Engineering, or a related technical field.
• 15+ years of experience in software engineering and application security architecture, including designing, securing, and operating distributed applications.
• Experience with application security frameworks such as OWASP Top 10, OWASP API Top 10, CWE/SANS 25, or zero-trust application patterns.
• Experience in identity and access governance including one or more of OAuth 2.0, OIDC, SAML, mTLS, SPIFFE/SPIRE, or fine-grained authorization models (RBAC, ABAC, ReBAC).
• Experience in at least one backend language: Python, Go, TypeScript/Node.js, Rust, or Java.
• Experience integrating security controls into cloud-native architectures such as Kubernetes, AWS/GCP/Azure, API gateways, or service meshes.

Technologies

• Model Context Protocol (MCP); LLM tool-calling workflows
• OpenAPI, TypeSpec, gRPC/Protobuf
• Open Policy Agent (OPA), Rego, Cedar
• OWASP Top 10, OWASP API Top 10, CWE/SANS 25, OWASP Top 10 for LLMs
• OAuth 2.0, OIDC, SAML, mTLS, SPIFFE/SPIRE
• RBAC, ABAC, ReBAC
• Python, Go, TypeScript/Node.js, Rust, Java
• Kubernetes, AWS, GCP, Azure, API gateways, service meshes
• SAST, DAST, IAST, software composition analysis
• Container image signing, SBOM tracking
• OPA/Rego (also listed separately), Semgrep, CodeQL, CVE

Benefits

• Medical, dental and vision insurance
• 401(k) plan with a Cisco matching contribution
• Paid parental leave
• Short and long-term disability coverage
• Basic life insurance
• Cisco restricted stock units that vest following continued employment with Cisco for defined periods
• 10 paid holidays per full calendar year
• 1 floating holiday for non-exempt employees
• 1 paid day off for employee’s birthday
• Paid year-end holiday shutdown
• 4 paid days off for personal wellness determined by Cisco
• Non-exempt employees: 16 days of paid vacation time per full calendar year, accrued at 4.92 hours per pay period for full-time employees
• Exempt employees: flexible vacation time off program with no defined limit (subject to availability and some business limitations)
• 80 hours of sick time off provided on hire date and each January 1st thereafter, and up to 80 hours of unused sick time carried forward
• Additional paid time away may be requested to deal with critical or emergency issues for family members
• Optional 10 paid days per full calendar year to volunteer
• For non-sales roles, employees may be eligible to earn annual bonuses subject to Cisco’s policies

Application window

The application window is expected to close on 10/30/2026.

Preferred qualifications

• Experience with the security implications of the Model Context Protocol (MCP) or similar AI tool-invocation interfaces
• Experience writing policy-as-code engines (Open Policy Agent, AWS Cedar, Oso/Polar) or custom linter/SAST rules (Semgrep, CodeQL)
• Active involvement in application security research, CVE publications, open-source security tooling, or industry working groups (OWASP, CNCF Security, OASIS)
• Relevant security certifications (for example, CISSP, CSSLP, CCSP, or AWS Certified Security)
• Experience evaluating and securing LLM-powered applications, tool-use execution loops, and RAG architectures