Senior Security Engineer

London Office - Hybrid: 4 days in the office, 1 day working from home

Role Overview

Our FinTech Client headquartered in London are currently seeking a Senior Security Engineer to embed security throughout their product development lifecycle. You'll work directly with engineering teams to identify and mitigate security risks through threat modeling, secure code reviews, and integrated security tooling across our web and mobile applications. This role is critical to establishing our secure development practices, implementing industry-standard SSDLC processes, and ensuring our financial products are resilient against evolving threats.

Key Responsibilities

Secure Development Lifecycle (SDLC) Implementation

• Design and implement secure software development practices
• Integrate security gates into CI/CD pipelines following DevSecOps principles
• Establish security quality gates and acceptance criteria
• Develop secure coding standards based on OWASP guidelines
• Create security architecture patterns and reference implementations

Security Code Reviews & Testing

• Conduct in-depth security code reviews for critical features
• Implement automated security testing (SAST, DAST, IAST, SCA)
• Configure and tune security scanning tools (Aquasec, Trivy, Dependabot, etc)
• Review cryptographic implementations against industry standards
• Validate authentication and authorization implementations
• Ensure compliance with OWASP ASVS (Application Security Verification Standard)

Threat Modeling & Risk Assessment

• Lead threat modeling sessions using STRIDE, PASTA, or similar frameworks
• Create threat models for new products and architectural changes
• Identify attack vectors specific to web and mobile platforms
• Develop abuse cases and security test scenarios
• Maintain threat intelligence for fintech-specific risks
• Document security requirements derived from threat models

Platform-Specific Security

• Web Applications: Implement defenses against OWASP Top 10 vulnerabilities
• Mobile Applications: Apply OWASP MASVS and platform-specific guidelines (iOS App Transport Security, Android Network Security Config)
• APIs: Implement API security best practices (rate limiting, authentication, input validation)
• Cross-platform session management and secure data storage

Security Tooling & Automation

• Build and maintain security testing pipelines
• Integrate security tools with GitHub Actions
• Develop custom security linters and pre-commit hooks
• Create automated vulnerability tracking and remediation workflows
• Implement secret scanning and dependency checking
• Build security dashboards and metrics reporting

Developer Enablement & Training

• Create secure coding guidelines for different technology stacks
• Develop a security champions program aligned with OWASP SAMM
• Conduct security training on platform-specific vulnerabilities
• Provide hands-on guidance during security incidents
• Build internal security libraries and frameworks
• Create threat modeling templates and playbooks

Required Qualifications

Technical Expertise

• 5+ years of application security experience
• Strong programming skills in multiple languages (Python, JavaScript/TypeScript, Golang)
• Deep understanding of security vulnerabilities across web and mobile platforms
• Hands-on experience with security testing tools and methodologies
• Expertise in secure coding practices and design patterns
• Experience with modern development frameworks (React, Angular, ReactNative, Flutter)

Security Domain Knowledge

• Expert knowledge of OWASP standards (Top 10, ASVS, SAMM, MASVS)
• Understanding of cryptographic principles and secure implementations
• Experience with threat modeling methodologies
• Knowledge of authentication standards (OAuth2, OIDC, WebAuthn)
• Familiarity with PCI-DSS, PSD2, and Strong Customer Authentication requirements
• Understanding of cloud-native security patterns

Code Review & Analysis Skills

• Ability to identify security vulnerabilities through manual code review
• Experience with static and dynamic analysis tools
• Understanding of common vulnerability patterns across languages
• Knowledge of secure architecture patterns and anti-patterns
• Ability to provide actionable remediation guidance

Professional Requirements

• Experience in financial services or high-security environments
• Strong communication skills to explain security risks to developers
• Ability to balance security requirements with development velocity
• Collaborative approach to working with engineering teams
• Technical writing skills for documentation and guidelines

Preferred Qualifications

• Experience with payment systems and transaction security
• Knowledge of mobile app protection
• Experience building security champions programs
• Background in penetration testing or security research

Key Projects & Initiatives

As a Senior Security Engineer, you'll lead critical security initiatives, including:

• Building threat modeling practice for all products
• Establishing automated security testing in CI/CD pipelines
• Creating platform-specific security standards and libraries
• Developing a security training curriculum for 200+ developers

What We Offer

• Direct impact on the security of products used by thousands of businesses
• Work with cutting-edge fintech products across multiple platforms
• Collaborate with talented engineers across 25+ countries
• Modern security tooling and testing infrastructure
• Investment in professional development and certifications
• Clear progression path to Staff/Principal roles

If you are interested in joining a truly dynamic organisation where you will play an integral part in shaping the company's security culture, please contact me for further details nazia@withintro.com.

intro Consulting Ltd are proud to represent this forward thinking FinTech client. We act as their trusted recruitment partner, connecting top talent with meaningful opportunities.