Start: July 2026
Duration: Initial contract until Dec 2026, with extension potential
Location: London / Hybrid 2 days onsite
Rate: Up to £750 per day Inside IR35
We are supporting a major UK financial services organisation on a significant payments modernisation programme and are seeking an experienced Lead Engineer with strong Kotlin expertise to help drive the transformation of critical payment services and platforms. This confidential engagement focuses on modernising payment gateway capabilities, API platforms, orchestration services, developer tooling, and in-person payments infrastructure. The successful candidate will play a key role in shaping the technical direction of the programme while contributing hands-on to the design and delivery of scalable, cloud-native solutions.
Responsibilities
- Lead the design and development of next-generation payment gateway capabilities using Kotlin
- Drive the modernisation of API and orchestration platforms
- Provide technical leadership across both discovery and delivery phases
- Define architecture, engineering standards, and best practices
- Mentor engineering teams and support technical decision-making
- Work closely with product, architecture, and business stakeholders
- Contribute deep payments domain knowledge to solution design and delivery
- Help shape the long-term technology roadmap for the payments platform
Key Skills Essential
- Strong commercial experience building backend platforms in Kotlin
- Experience leading engineering teams and delivering complex distributed systems
- Payment gateway, payments platform, or transaction processing experience
- API design and development experience
- Financial services or highly regulated industry experience
- Strong understanding of modern software architecture and engineering practices
- Ability to provide technical leadership in large-scale transformation programmes
Desirable
- Java experience (legacy platform integration and migration a bonus)
- TypeScript
- Experience with cloud-native architectures, microservices, and event-driven systems
- Exposure to developer platforms and engineering enablement initiatives
This is an excellent opportunity to join a high-profile payments transformation programme where Kotlin is at the heart of the modernisation strategy, helping to build the next generation of payment capabilities within a leading financial services environment.
