Application Security Engineer: AI-First Security Leader

Fin. The highest performing Customer Agent; Greater London; Hybrid; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Equity

Lunch provided

Health insurance

Pension

Cycle-to-Work

MacBook provided

Job summary

Fin is transforming security for AI-powered customer experiences. The Security Engineering team owns tier-zero security services, including authentication, SAML/SSO, and logs, while partnering with engineering to make secure development the default.

Join a fast-growing SaaS company driving AI-first security, threat detection, and continuous monitoring to protect Fin and its customers. Hybrid work supports collaboration and delivery velocity.

Qualifications

• Proven app security or security engineering experience in a SaaS environment.
• Strong software engineering skills for production systems.
• Deep understanding of modern app security threats and secure SDLC.
• Experience designing authentication, authorization, identity, or enterprise security capabilities.
• Experience architecture reviews and security assessments for complex systems.
• Hands-on security incident response leadership.
• Strong programming and automation skills.
• Comfort with AI-assisted development tools.
• Clear communication with engineering teams.
• Pragmatic balance of security, customer impact, and velocity.

Responsibilities

• Own tier-zero security capabilities for customers.
• Design and evolve authentication, SAML/SSO, permissions, logs, and enterprise controls.
• Partner with engineering across the SDLC to build secure products.
• Perform architecture reviews and threat modelling for new features.
• Build security tooling, automation, and developer-facing blocks.
• Contribute to secure development standards and practices across Fin.
• Lead security initiatives across the SDLC to address risks early.
• Participate in on-call rotation and lead incident response.
• Drive security initiatives from definition to measurable outcomes.
• Collaborate with teams building AI-powered products to mitigate risks.
• Support secure adoption of AI-assisted development tools.

Skills

App Security

Security Engineering

SaaS Security

Threat Modelling

Incident Response

Programming

AI Tools

Security Architecture

Engineering Collaboration

Security Automation

Tools

SAML/SSO

Audit tooling

Threat modelling tools

Job description

Fin is transforming security for AI-powered customer experiences. The Security Engineering team owns tier-zero security services, including authentication, SAML/SSO, and logs, while partnering with engineering to make secure development the default.

Join a fast-growing SaaS company driving AI-first security, threat detection, and continuous monitoring to protect Fin and its customers. Hybrid work supports collaboration and delivery velocity.