Senior Software Developer

This London-based role is part of Verifone's global payment gateway platform, where engineering decisions directly impact the reliability, security, and performance of high-volume financial transactions worldwide. You will work on backend services that sit at the core of payment processing, balancing scalability, data consistency, and security in a highly regulated environment., The role is ideal for a senior backend developer who enjoys working on complex distributed systems, modern Java platforms, and cloud-native architectures, and who takes ownership of systems that must perform reliably under real-world load., We are seeking a Senior Developer based in London to design, build, and operate backend services for our global payment gateway system. You will develop high-performance, secure microservices using Java and Spring Boot, collaborate closely with platform, product, and infrastructure teams, and help ensure our systems scale reliably across regions and partners.

• Spring Boot
• Spring Web (REST APIs)
• Spring Data
• Spring Security with JWT / OAuth2

Architecture & System Design

• Microservice-based architectures
• Clean code practices and SOLID principles
• Experience designing scalable, fault-tolerant backend services
• Strong understanding of security, authentication flows, and data protection

API & Data

• RESTful API design using JSON and HTTP standards
• API versioning strategies
• MongoDB / NoSQL experience, including:

• Data modeling
• Indexing strategies
• Performance tuning

• Experience with Java concurrency, streams, and performance optimization

Cloud & Infrastructure

• AWS services including EC2, ECS/EKS, S3, RDS and/or DynamoDB, and CloudWatch
• Docker and containerized deployments
• CI/CD pipelines and Git-based workflows

Testing & Engineering Practices

• Unit and integration testing using JUnit and Mockito
• Strong focus on testability, quality, and maintainability
• Experience working in Agile / Scrum environments

Preferred Skills and Experience

Payments & Domain Experience

• Background in fintech or payments
• Experience handling transactions, payment flows, and financial data
• Understanding of high-availability, security, and data consistency trade-offs

Eventing & Distributed Systems

• Exposure to event-driven architectures
• Messaging or streaming technologies such as:

• Kafka
• AWS SQS
• Similar eventing systems

Platform & Operations

• Advanced experience with AWS, Docker, and CI/CD practices
• Production experience operating distributed systems at scale
• Strong ownership mindset for services running in production

For more than 30 years, Verifone has been a global leader in electronic payment technology. We work with leading retailers, merchants, banks, and technology partners to deliver secure, reliable, and innovative payment solutions worldwide. Verifone offers a fast-paced, collaborative environment focused on engineering excellence, customer impact, and continuous innovation. We are proudly an in-office organization and currently support a hybrid work model, which is reviewed regularly.