Principal Software Engineer - Full Stack (Java)

About the role

The Customer Service Network Domain is looking for a Principal Software Engineer to lead a major three-year transformation of its ATM network, covering ATM software, routing and switching, reconciliation, real-time data and cash management. The work includes a greenfield ATM switching platform and a move toward a cloud-native architecture, with opportunities to define the target architecture and mentor other engineers.

Key responsibilities

• Lead the design of resilient cloud infrastructure and the integration of a new Java-based ATM switch
• Modernise complex legacy estates, reduce technical debt and simplify architecture while protecting reliability
• Champion Terraform, quality engineering, fail-safe design, REST APIs and modern observability patterns
• Use AI-powered engineering and agentic tooling to accelerate reverse engineering, requirement discovery, prototyping and delivery
• Influence engineering direction across the domain and mentor other engineers

Required profile

• Principal Engineer-level systems thinking and end-to-end architecture expertise
• Deep Java and Spring Boot expertise with full-stack breadth, ideally TypeScript, React, Next.js and Node.js
• Experience designing and delivering cloud-native, distributed systems at scale
• Proven track record of large-scale modernisation of legacy environments
• Strong integration engineering experience and hands-on technical leadership

Required skills

• Front-end: React, Next.js, TypeScript
• Back-end: Java, Spring Boot, microservices, REST APIs
• Cloud: AWS, Terraform, AWS CDK, AWS CloudFormation
• Event-driven: Apache Kafka
• Databases: Oracle PL/SQL, MongoDB, AWS NoSQL services
• CI/CD and quality: GitHub Actions, Specmatic, unit, integration and E2E testing
• Observability: Prometheus, Grafana, PagerDuty