Staff Security Engineer: AI & App Security Leader

Marcura; United States; Hybrid; USD 150,000 - 210,000; Full time

Benefits offered by this job

Competitive salary and bonus

Inclusive onboarding experience

Marcura Wellness Zone

Global opportunities

Diverse, supportive work culture

Job summary

Marcura is seeking a Staff Security Engineer for AI & Application Security. You will own security engineering end-to-end, directly perform penetration testing and AI red team exercises, and define secure-by-design patterns for LLM and agentic systems.

You will govern architecture reviews, risk prioritisation, and collaboration with product, engineering, data and operations teams. You will manage external testing partnerships (MDR) and internal testing programs, ensuring security is integrated

Qualifications

• 8+ years total experience in security engineering across offensive and defensive domains.
• At least 4 years hands-on offensive experience: leading and executing tests across web, APIs, cloud, networks.
• Defensive engineering experience: hardening cloud and application environments, building or tuning detections.
• Proven experience securing LLM or AI systems in production, including prompt injection, jailbreaks, data exfiltration.
• Experience as a first, sole or founding security hire, or building a security capability from a standing start.
• Track record influencing architecture and design decisions across engineering and product teams, not only reporting findings.
• Experience supporting or leading security incident response in a production environment.
• Experience owning MDR or managed SOC provider — onboarding telemetry, validating and tuning detection coverage.
• Experience scoping, commissioning external penetration tests, and integrating third party findings into remediation.
• Experience in regulated B2B, fintech, maritime or logistics environment preferred.

Responsibilities

• Define security strategy, roadmap and prioritisation for the company.
• Lead secure architecture and design reviews across products and cloud.
• Advise on AI and LLM security and build an enterprise-wide security framework.
• Develop and maintain security standards for AI/LLM systems.
• Manage internal penetration testing programmes and external pentest ownership.
• Oversee AI red teaming, adversarial testing and defensive hardening.
• Harden applications and cloud infrastructure; implement identity and data protection controls.
• Coordinate MDR partnership (eSentire) and validate detections and response.
• Drive detection engineering, incident response and remediation processes.
• Ensure third-party, vendor and model assurance aligns with risk appetite.
• Foster security culture and enable engineering teams through tooling and guidance.

Skills

Offensive testing

Defensive engineering

LLM security

Penetration testing

Red teaming

Cloud security

Data protection

Security governance

Threat modeling

Threat hunting

Job description

Marcura is seeking a Staff Security Engineer for AI & Application Security. You will own security engineering end-to-end, directly perform penetration testing and AI red team exercises, and define secure-by-design patterns for LLM and agentic systems.

You will govern architecture reviews, risk prioritisation, and collaboration with product, engineering, data and operations teams. You will manage external testing partnerships (MDR) and internal testing programs, ensuring security is integrated