Staff Security Engineer – Platform Security

NJF Global Holdings Ltd; Greater London; On-site; GBP 120,000 - 180,000; Full time

Job summary

NJF Global Holdings Ltd. is seeking a Staff Security Engineer focusing on Platform Security in London.

You will design and implement security controls for AI platforms, cloud infrastructure, and developer tooling, embedding secure-by-default practices across engineering teams. You will contribute to security patterns, identity controls, telemetry, and incident readiness while overseeing secrets and vulnerabilities.

Qualifications

• 8+ years in security engineering, software or platform engineering.
• Strong software engineering skills; building production systems and security controls.
• Deep expertise in cloud/platform security, app security or security architecture.
• Experience with AI/ML platforms, LLM infra, inference systems or agent-based tech.

Responsibilities

• Design and build security controls across AI platforms, developer tooling and cloud infra.
• Embed secure-by-default controls into platform teams' work.
• Define security patterns, standards and identity/permissioning for AI systems.
• Build telemetry, auditability and investigation capabilities for AI/automation.
• Own secrets management, vulnerability management and component provenance.
• Threat model AI platforms and cloud infra; translate risks into engineering solutions.

Skills

Security engineering

Software engineering

Cloud security

AI security

CI/CD security

Independent decision making

Security architecture

Education

CS/Software Engineering degree

Job description

We are partnering with a leading technology-driven investment firm to hire a Staff Security Engineer – Platform Security in a highly technical, engineering-led environment.

The team is building the security foundations that enable the organisation to adopt advanced AI technologies quickly and safely. The role sits at the intersection of security engineering, software engineering, cloud infrastructure, platform security and AI, with significant scope to shape security practices in an emerging area.

Platform & AI Security

As a Staff Security Engineer, you will:

• Design and build security controls across AI platforms, inference systems, developer tooling and cloud infrastructure
• Embed secure-by-default controls into the platforms and systems engineering teams already use
• Define security patterns and standards for teams building and deploying AI-enabled systems
• Define and enforce identity, access and permissioning for AI agents and automated systems
• Build telemetry, auditability and investigation capabilities around AI and automated activity
• Secure AI development environments, developer tooling, plugins, dependencies and model supply chains
• Own areas including secrets management, vulnerability management and component provenance
• Threat model AI platforms, cloud infrastructure, developer tooling and emerging attack surfaces
• Translate identified security risks into practical engineering solutions and deliver remediation directly
• Identify gaps in security coverage and prioritise improvements based on risk and delivery constraints
• Help establish the technical direction, engineering patterns and security practices for a growing security function

What We’re Looking For

• 8+ years of experience across security engineering, software engineering, platform engineering or a closely related technical discipline
• Strong software engineering skills, with experience building and deploying production systems and security controls
• Deep expertise in at least one area such as cloud/platform security, application security or security architecture
• Working breadth across broader security engineering disciplines
• Hands-on experience securing cloud environments and CI/CD pipelines
• Experience with AI/ML platforms, LLM infrastructure, inference systems or agent-based technologies
• Strong academic background in Computer Science, Software Engineering or a related technical discipline
• Ability to operate independently and make sound security decisions in emerging and ambiguous areas
• Experience using AI-assisted development and coding tools in day-to-day engineering work
• Experience in regulated, financial services or other high-security environments
• Background in detection engineering, incident response or security operations
• Experience establishing security practices or capabilities within a new or rapidly developing function
• Strong interest in the security implications of emerging AI technologies

This is an opportunity to join a highly technical, engineering-led environment at an early stage of its AI security journey, with significant ownership and scope to influence how AI is adopted securely across the organisation.