Your role What you'll be doing What We Need Corpay Cross‑Border is seeking a Full Stack Senior Software Developer to join our agile development team in London. In this role, you will advance our core international payment processing systems—driving innovation in forex and e‑commerce software that powers global payments. You’ll report to the Software Development Manager and collaborate closely with Product Owners, QA Engineers, and Scrum Masters. How We Work As a Full Stack Senior Software Developer, you will thrive in a hybrid environment, splitting your time between our London office and remote work. Corpay Cross‑Border will set you up for success by providing: Assigned desk in our London office Company‑issued development hardware and software licenses Formal, hands‑on onboarding and ongoing training Role Responsibilities Collaborate with business stakeholders to gather requirements and clarify technical questions Decompose features into actionable tasks, estimate effort, and deliver on sprint commitments Design, develop, and maintain scalable front‑end and back‑end solutions using .NET, C#, JavaScript, and TypeScript Write clean, efficient, and maintainable code following Agile methodologies, unit testing, and CI/CD best practices Participate in peer code reviews to ensure code quality and shared ownership Build and consume HTTP‑based Web APIs and integrate third‑party services Troubleshoot, debug, and optimize existing systems for reliability and performance Contribute to architectural discussions around distributed applications, service buses, multi‑threading, and parallel processing Mentor junior developers and share knowledge of legacy systems (VB.NET, VB6) as needed Qualifications & Skills Experience: 10 years of professional software engineering in enterprise environments Education: B.S. in Computer Science, Engineering, or equivalent Technical Expertise: .NET design and development for desktop and web applications Proficiency in C#, JavaScript, and TypeScript Deep understanding of MS SQL Server, advanced T‑SQL, and relational database design Unit testing frameworks (e.g., xUnit, Moq) and test‑driven development Building and consuming RESTful APIs Familiarity with distributed systems, service buses, and parallel processing Nice to have: experience with VB.NET, VB6, and external vendor integrations Attributes: Product‑focused mindset with the ability to translate business needs into technical solutions Commitment to delivering high‑quality, reliable, and scalable software Strong collaboration and communication skills in cross‑functional teams Adaptability to scope requirements and estimate timelines in ambiguous contexts Continuous learner who stays current with emerging technologies Benefits & Perks Holiday entitlement: 25 days per annum 8 bank holidays Additional leave: Option to buy or sell 5 days annual leave once a year during the annual benefits enrolment window Pension: Minimum 3% employee contribution → up to 5% employer match from Corpay Private Medical Insurance: Vitality plan with zero excess (we cover the £250 excess charge) Benefits portal (Gratitudes): Flexible discounts and savings (e.g., 4–5% at major supermarkets) LinkedIn Learning: Free, unlimited access to courses and learning paths Our Company & Purpose Corpay is a global technology organization leading the future of commercial payments. Backed by FLEETCOR Technologies, Inc. (NYSE: FLT), a Fortune 1000 & S&P 500 firm, we power smarter ways for businesses to pay fuel, general payables, tolls, lodging, and more. Millions of users in over 80 countries rely on our solutions for fast, secure, and compliant payments. We embrace five core values—integrity, collaboration, innovation, execution, and people—to foster career development, wellness, and community engagement. Corpay is committed to diversity, equity, and inclusion, welcoming individuals of all backgrounds, cultures, and perspectives. All employment offers are contingent on satisfactory pre‑employment screening (identity, reference, criminal, financial, and sanctions checks). Equal Opportunity Employer Corpay provides equal employment opportunities to all applicants without regard to race, color, gender, religion, national origin, age, disability, veteran status, or any other protected characteristic under federal, local, or state law. Notice to Agency and Search Firm Representatives: Corpay does not accept unsolicited resumes from agencies without a signed search agreement. About Corpay Corpay is a global technology organisation that is leading the future of commercial payments with a culture of innovation that drives us to constantly create new and better ways to pay. Our specialized payment solutions help businesses control, simplify, and secure payment for fuel, general payables, toll and lodging expenses. Millions of people in over 80 countries around the world use our solutions for their payments. All offers of employment made by Corpay (and its subsidiary companies) are subject to the successful completion of satisfactory pre-employment vetting by an independent supplier (Experian). This is in accordance with Corpay's Resourcing Policy and include employment referencing, identity, adverse financial, criminal and sanctions list checks. We do this to meet our legal and regulatory requirements. Corpay is dedicated to encouraging a supportive and inclusive culture among our employees. It is within our best interest to promote diversity and eliminate discrimination in the workplace. We seek to ensure that all employees and job applicants are given equal opportunities. Notice to Agency and Search Firm Representatives: Corpay will not accept unsolicited CV's from agencies and/or search firms for this job posting. Resumes submitted to any Corpay employee by a third party agency and/or search firm without a valid written & signed search agreement, will become the sole property of Corpay. No fee will be paid if a candidate is hired for this position as a result of an unsolicited agency or search firm referral. Thank you.