Senior Software Engineer Location: Belfast (Hybrid) The Mission Build secure, reliable, high-throughput gateway services that process real financial transactions without failure. You own delivery of backend features end-to-end from design through production with security and quality built in from day one. What Youll Own ?? Backend Delivery Design and build gateway components in C# / .NET Deliver secure RESTful services supporting real-time transactions Work with high-volume transactional databases Contribute across the full SDLC analysis, design, implementation, testing, release Support production systems and resolve live issues decisively ?? Security by Default Deliver features aligned to PCI DSS requirements Apply OWASP secure coding standards Implement secure authentication flows (MFA, session validation, secure cookies) Contribute to security scans and vulnerability remediation Strengthen API and browser security controls (e.g., CSP, input validation) ?? Engineering Standards Practice TDD / BDD as standard Write meaningful automated tests Participate in thorough code reviews Contribute to CI/CD pipeline quality Use monitoring tools to diagnose and prevent production issues ?? Team Contribution Mentor mid-level engineers Contribute to sprint planning and estimation Raise technical risks early Improve processes where you see friction What You Bring Experience 5 years backend software engineering Experience building secure, transaction-driven systems Experience working in regulated or compliance-focused environments Technical Depth Strong C# / .NET experience Strong SQL and transactional database knowledge Experience working in CI/CD environments Solid understanding of secure authentication and session management How You Think Quality over shortcuts Security is part of the build, not an afterthought Ownership of outcomes, not just tickets Clear communication and pragmatic delivery Calm under production pressure What Success Looks Like Secure features delivered on time Strong automated test coverage Stable production releases Reduced defect leakage Growing technical confidence within the team Skills: C# .Net SQL