Senior Backend Engineer - Payin Platform

In this role you will design, build, and maintain backend services and RESTful APIs powering Wise’s Direct Debit and Payin platforms. You’ll work on a high-volume, cloud-based payments stack, optimizing for cost, reliability, and security across global partners. You’ll collaborate with product, design, and tech teams to deliver scalable funding and pre-authorization use-cases. This is a chance to contribute to a mission-driven platform that moves money faster and with lower friction for customers worldwide.

• Design, develop, test, and maintain backend services on AWS
• Build and maintain RESTful APIs serving web and mobile users
• Power the card pay-in method and scale ~$1B in monthly payments
• Design schemas and optimise PostgreSQL queries for high-volume data
• Implement event-driven architectures using Apache Kafka for asynchronous processing
• Develop and maintain a payment orchestration system routing across providers to optimize cost and reliability
• Write automated tests (unit/integration/e2e) to ensure reliability of financial systems
• Conduct code reviews to ensure quality, security, and standards
• Participate in on-call rotations to monitor Tier 2 critical services
• Collaborate with cross-functional teams to deliver projects
• Identify and resolve performance bottlenecks and technical debt
• Ensure security practices align with financial regulations

• collaboration across product, design, and engineering teams
• communication of complex technical topics
• ability to work under production incident conditions
• RESTful APIs
• AWS cloud infrastructure
• PostgreSQL and SQL optimization