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 You’ll 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