Senior Full-Stack Engineer

Job Role: Senior Full-Stack Engineer
Employment Type: Contract
Start Date: January 2027
Contract Length: 9-12 months
Remote/Hybrid/Office: Hybrid
Day Rates: TBC

About us
FT Select is a niche technology search and selection company, specialising in recruiting elite Sales Executives and high-end Technology specialists for high-growth tech businesses.________________________________________
About the Company
A well-known leading global financial services organisation.
Description of Role:
Fixes application-level security vulnerabilities across platform repositories. Works directly within platform codebases via pull requests, always under the review and ownership of the relevant Engineering Lead. Focuses on clearing the most impactful application-layer findings quickly and creating reusable fix patterns.
Key Responsibilities:
• Upgrade vulnerable libraries and frameworks.
• Fix input validation, authentication, and authorisation flaws.
• Resolve API security issues and insecure token/session handling.
• Address error handling, information leakage, and file upload vulnerabilities.
• Fix cross-site scripting, injection-related, and browser security control issues.
• Refactor insecure legacy code patterns.
• Implement front-end security headers and content security policies.
• Create reusable fix patterns and upgrade guides for sharing across teams.
Required Skills:
• Senior-level full-stack development experience (5+ years).
• Strong knowledge of secure coding principles (OWASP Top 10).
• Experience working across multiple languages/frameworks (e.g. .NET, Node.js, React, Python).
• Comfortable working in unfamiliar codebases and raising pull requests.
• Experience with SAST tooling and interpreting scan findings.
• Ability to work at pace across multiple teams simultaneously.
• Security-aware mindset with a developer-first approach to remediation.