Principal Software Engineer

Why Verifone

For more than 40 years Verifone has established a remarkable record of leadership in the electronic payment technology industry. Verifone has one of the leading electronic payment solutions brands and is one of the largest providers of electronic payment systems worldwide.

Verifone has a diverse, dynamic and fast paced work environment in which employees are focused on results and have opportunities to excel. We take pride in the fact that we work with leading retailers, merchants, banks, and third party partners to invent and deliver innovative payments solution around the world. We strive for excellence in our products and services, and are obsessed with customer happiness. Across the globe, Verifone employees are leading the payments industry through experience, innovation, and an ambitious spirit. Whether it’s developing the next platform of secure payment systems or searching for new ways to bring electronic payments to new markets, the team at Verifone is dedicated to the success of our customers, partners and investors. It is this passion for innovation that drives each one of our employees for personal and professional success.

About The Role

We are seeking a Principal Software Engineer based in London to provide technical leadership across backend services supporting our global payment gateway system. You will design and evolve core platform capabilities, guide architectural decisions across microservices, and mentor engineers while remaining hands‑on with critical systems built using Java and Spring Boot.

This role sits at the heart of Verifone’s global payment gateway platform. You will help shape the technical direction of systems responsible for processing high‑volume, mission‑critical financial transactions worldwide.

At this level, the role goes beyond feature delivery. You will drive architectural decisions, set engineering standards, and influence how teams design, build, and operate secure, scalable backend systems. Success in this role is defined by technical leadership, sound judgment in complex trade‑offs, and ownership of systems that must perform reliably under real‑world load and regulatory constraints.

You will work closely with senior engineering, platform, product, and infrastructure partners to ensure our systems scale globally, remain secure, and meet the highest standards for availability and performance.

Our Commitment

Verifone is committed to creating a diverse environment and is proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. Verifone is also committed to compliance with all fair employment practices regarding citizenship and immigration status.

Required Skills and Experience Needed

Programming Languages

• Java 17 or higher

Frameworks and Libraries

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

Architecture & System Design

• Deep experience designing and operating microservice‑based architectures
• Strong application of clean code practices and SOLID principles
• Ownership of system‑level architecture and cross‑service design decisions
• Strong understanding of security, authentication flows, and data protection in distributed systems

API & Data

• Design and governance of RESTful APIs, JSON, and HTTP standards
• API versioning and backward‑compatibility strategies
• MongoDB / NoSQL expertise, including:
  • Data modeling
  • Indexing strategies
  • Performance optimization
• Advanced experience with Java concurrency, streams, and performance tuning

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
• Experience designing systems for scalability, resilience, and operability

Testing & Engineering Practices

• Strong unit and integration testing practices using JUnit and Mockito
• Ownership of quality standards, testability, and CI discipline
• Experience working in Agile / Scrum environments and influencing engineering best practices

Experience Level

• Principal‑level backend engineering experience building and operating large‑scale, high‑performance systems
• Approximately 8+ years of backend development experience, with several years working on production Java and Spring Boot services
• Proven experience owning architecture and technical direction for critical backend platforms
• Extensive production experience with MongoDB, including modeling, indexing, and performance optimization

Bonus Skills and Experience

Payments & Domain Expertise

• Background in fintech or payments
• Experience with payment processing, transactions, and financial data
• Strong understanding of high‑availability, security, and data‑consistency trade‑offs

Eventing & Distributed Systems

• Experience with event‑driven architectures
• Messaging or streaming technologies such as:
  • Kafka
  • AWS SQS
  • Similar eventing systems

Platform & Technical Leadership

• Deep experience with AWS, Docker, and CI/CD practices
• Proven ability to mentor engineers and raise the technical bar across teams
• Strong sense of ownership for systems running in production