Senior Software Engineer II - Payin Platform - Backend (Java)

In this Senior Software Engineer role, you will strengthen Wise’s Payin Platform, enabling seamless entry of funds across multiple payment methods. You’ll build scalable Payin Session and Payment abstractions used by many product teams, focusing on correctness, reliability, and robust APIs. This high-impact platform work supports growth across products and millions of transactions, shaping how money moves globally. You’ll collaborate with cross-functional teams and contribute to a data-driven, customer-focused engineering culture.

• Starting salary: 111K - 145K GBP
• RSUs
• Wise Benefits
• Hybrid work arrangement

• Design and implement Payin Session and Payment abstractions to enable scalable integrations across products
• Develop high-volume, reliable platform components with strong API design
• Collaborate with product teams to support multiple payment methods (Cards, Apple Pay, Google Pay, Balance, Bank Transfer, etc.)
• Ensure code quality through testing strategies (unit/integration) and code reviews
• Own end-to-end delivery of projects, driving them to meet business goals
• Promote best practices, processes, and culture improvements within the team

• 5+ years of experience in Java, Kotlin, Python or Go
• Strong experience with Spring framework
• Relational databases and distributed/concurrent systems (Kafka)
• Excellent cross-team communication and ability to discuss complex topics with technical and non-technical audiences
• Experience with testable code and testing strategies (unit, integration)
• Strong coding practices, code reviews, and open feedback culture
• Customer-focused mindset with data-driven decision making
• Ability to work independently with end-to-end ownership

• cross-team communication
• strong ownership
• customer focus
• Java / Kotlin / Python / Go (multi-language proficiency)
• Spring framework
• Relational databases