Staff Application & Product Security Engineer

You will be the most senior hands-on application security engineer at Cleo, owning both how security is built into our products from design through release and the security posture of the products we ship, both on-premise and SaaS, as our customers experience them. This is a Staff-level individual contributor role with real program ownership: you set the standards, build the guardrails, and work directly with engineers in the code. You report to the CISO and partner daily with Engineering, and our Cloud Security team.

Responsibilities

Own and mature the Secure Development Lifecycle (SSDLC), including security requirements, threat modeling, and design reviews for high-risk product changes, APIs, and integrations; Run and tune SAST, SCA, secrets detection, container, and IaC scanning; Build reusable secure patterns, reference implementations, and policy-as-code controls; Own developer security enablement, including the Security Champions meeting, engineering security training campaigns, a named champion in every squad, remediation guidance, office hours, and self-service security capabilities; Run risk-based triage, remediation, and verification for application and product vulnerabilities, including SLAs, escalation, and exceptions; Reproduce externally reported vulnerabilities against running product instances and validate patches before release; Own the penetration testing program, including scoping and coordinating third-party engagements and performing targeted testing; Run the Vulnerability Disclosure Program, including researcher communications and coordinated disclosure; Coordinate the CVE lifecycle for Cleo products and support product-security incident response; Own application and product-security controls in the NIST CSF 2.0 program, including maturity tracking and audit evidence; Own the security posture of products across SaaS and customer-hosted deployments, including secure defaults, authentication and session controls, RBAC and tenant isolation, admin data access, and hardening guidance; Own the Product Security Roadmap with Product Management, the CTO, and Architecture, including SSO/SAML upgrades, the in-app RBAC redesign, endpoint-level access control, and customer-requested controls; Act as technical owner for customer-facing product security, including triaging scan findings and pentest reports, answering security RFIs, and authoring advisories, release notes, and hardening documentation; Own threat modeling and security review for LLM-enabled features, AI agents, and AI-assisted development workflows; Build controls for prompt injection, sensitive data exposure, insecure output handling, excessive agency, insecure tool integrations, and AI supply-chain risk; Apply the OWASP Top 10 for LLM Applications and the NIST AI Risk Management Framework across product and engineering

Requirements

6+ years in application security, product security, or secure software engineering, including experience building or maturing an AppSec program across multiple engineering teams; Strong proficiency in an object-oriented programming language is required, with Java preferred; Ability to read, debug, and write production-quality code, and comfort working across languages such as TypeScript, Python, or Go; Deep knowledge of application attack surfaces: authentication, authorization, API security, business-logic flaws, and modern service architectures; Hands-on experience integrating and tuning SAST, SCA, and secrets scanning in GitHub and CI/CD pipelines; Hands-on exploit reproduction and patch validation against a running Java web application, including confirming fixes and writing up findings for researchers and customers; Coordinated disclosure experience with external security researchers and customers, including holding an embargo timeline and driving a CVE to publication; Product security experience on shipped software with an installed base, including secure defaults, hardening guidance, customer-facing advisories, security release notes, and turning customer scan reports or RFIs into fix-or-explain responses; Experience running threat modeling, design reviews, and manual security testing, and working directly with developers through remediation; Clear communicator who can turn technical risk into engineering guidance for developers and executives, and hold a release-gating decision with Engineering leadership when warranted

Nice to have

Securing LLM applications, AI agents, or AI-assisted development tools; SBOM (CycloneDX/SPDX), VEX, artifact signing, and SLSA; AWS, Kubernetes/EKS, Terraform, Jenkins; Snyk, GitHub Advanced Security, Semgrep, Burp Suite; NIST CSF 2.0, OWASP SAMM/ASVS, NIST SSDF; supporting SOC 2 or ISO 27001 audits; CSSLP, OSWE, GWAPT, AWS Security, or comparable certifications; Enterprise software with both SaaS and customer-hosted deployment models; SSO/SAML, RBAC design, and multi-tenant isolation; MFT/EDI or other B2B integration products

Benefits

Compensation of $160,000 to $180,000 plus bonus opportunity; Healthcare, dental, and vision coverage; Flexible PTO; Culture of support encouraging life-work balance; 401k match; FSA and HSA options; Employee Assistance Program; Paid parental leave; Remote work environment; Accelerated title and salary growth potential