Senior Java Developer

Role overview Lead the design and delivery of Java services for payment products, with hands-on ownership of integrations with MPGS and Visa Cybersource. Shape secure transaction flows from checkout and authentication through settlement and reconciliation, while working with finance, risk, and operations teams and helping other engineers make sound technical decisions.

Responsibilities - Design and maintain payment APIs using Java and Spring Boot, including integrations with both gateways. - Manage transaction states, idempotency, retries, duplicate prevention, and recovery when a gateway response is unclear. - Build tokenisation, 3-D Secure, authorisation, capture, void, refund, and gateway-notification flows. - Maintain auditable transaction records and ledger integrations; support settlement reconciliation and exception handling. - Apply payment security practices, protect credentials, and prevent sensitive card data from appearing in application logs. - Investigate payment incidents, review performance, improve automated tests, and mentor engineers.

Requirements - At least five years building production Java applications, including substantial fintech or payment-processing experience. - Production integration experience with both MPGS and Visa Cybersource. - Strong Spring Boot, SQL, and API design skills. - Deep knowledge of card-payment lifecycles, 3-D Secure, tokenisation, settlement, reconciliation, and chargebacks. - Experience protecting financial data integrity in concurrent, distributed systems, including idempotency and fault recovery. - Working knowledge of PCI DSS-aware engineering and secure credential handling. - Confidence with automated testing, Docker, and CI/CD, plus experience guiding developers and communicating clearly.

Nice to have - Experience with acquiring banks, payment orchestration, or multi-currency settlement. - Familiarity with fraud controls, dispute handling, or event-driven financial systems.