Senior Backend Engineer - Payin Platform at Wise
United Kingdom
Posted
on-site · full-time · Visa sponsorship
Responsibilities:
- Design, implement, test, and maintain backend services in Java/Kotlin using Spring Boot on AWS.
- Build and operate high-throughput RESTful APIs serving web and mobile clients.
- Develop and optimise the card pay-in flow and other payin methods that handle high transaction volumes.
- Design schema and write performant SQL for PostgreSQL to handle transactional workloads.
- Build and maintain event-driven systems using Apache Kafka for asynchronous financial events.
- Implement and evolve payment orchestration to route payments across providers for cost and reliability.
- Write automated tests (unit, integration, end-to-end) and participate in code reviews.
- Participate in on-call rotations, triage incidents, and resolve production issues for tiered services.
- Collaborate with product, design, analytics, and other engineering teams to deliver cross-functional features.
- Identify and remediate performance bottlenecks, scalability limits, technical debt, and security issues.
Requirements:
- Strong production experience with Java and/or Kotlin and Spring Boot.
- Proven experience building and operating cloud services on AWS.
- Solid knowledge of relational databases (PostgreSQL) and writing/optimising SQL.
- Experience with Kafka or similar event streaming platforms and event-driven design.
- Background in payment systems, payment orchestration, or fintech services preferred.
- Familiarity with REST API design, scalability patterns, and distributed systems concepts.
- Demonstrable testing practices (unit, integration, end-to-end) and code review discipline.
- Experience with on-call responsibilities and incident response.
- Good understanding of security and compliance concerns when handling financial data.