Payment Systems Engineer Job Description Template

The payment systems engineer builds the software that moves money, covering authorisation, settlement, reconciliation and the handling of the many ways a payment can fail. Correctness matters absolutely, since duplicate or lost transactions are real financial loss, and the systems have to remain correct under retries, timeouts and partial failure.

Typical Duties and Responsibilities

• Build and maintain payment processing services
• Integrate with payment processors, card networks and banking rails
• Implement idempotency so that retries cannot double charge
• Build reconciliation processes against processor and bank records
• Handle refunds, chargebacks, disputes and partial captures
• Implement retry and failure handling for transient errors
• Monitor payment success rates and investigate declines
• Support compliance requirements including PCI DSS obligations
• Build reporting on payment volumes, fees and failures
• Investigate and resolve discrepancies in money movement

Education

• Bachelor’s degree in computer science or a related field

Required Skills and Experience

• 3+ years building payment or financial transaction systems
• Deep understanding of idempotency and exactly once semantics in practice
• Experience integrating with payment providers and their failure modes
• Strong backend engineering in a language such as Java, Go, Python or C#
• Experience building reconciliation processes
• Understanding of PCI DSS scope and its implications
• Careful approach to data consistency and transactional integrity
• Good observability practice for money movement

Preferred Qualifications

• Experience with card network or ACH integration
• Knowledge of ledger design and double entry accounting