Join a leading UK retail organisation transforming their payments platform with cutting-edge technology and high-scale architecture.
Salary: £400 - 415 per day
Principal Java Engineer (Individual Contributor)
6-Month Contract | Outside IR35 | Paddington (3 days/week)
We are partnering with a leading UK retail organisation on a significant payments and platform transformation. We seek a Principal Java Engineer to join as a hands-on individual contributor, playing a pivotal role within a dynamic engineering team.
This technically demanding position centres on designing, building, and scaling high-volume, mission-critical payment systems. You will remain deeply involved in coding while influencing design and technical direction.
The Role:
As a Principal Java Engineer, you will design and develop scalable backend services that facilitate secure payment transactions at scale. The environment is modern, cloud-native, and prioritises event-driven architecture and high performance.
Key Responsibilities:
- Design and develop backend services using Java (Spring Boot or Micronaut)
- Build systems supporting secure, high-volume payment transactions
- Develop integrations with payment gateways, acquiring banks, and fraud prevention tools
- Operate within event-driven microservices architectures (Kafka)
- Contribute to system design and resolve complex technical challenges
- Write clean, maintainable, and high-quality code
Cloud and DevOps:
- Build and maintain cloud-native systems (Azure preferred)
- Utilise Terraform and Kubernetes for infrastructure provisioning and orchestration
- Work with CI/CD pipelines (GitHub Actions)
- Support monitoring, alerting, and system observability
Security and Compliance:
- Implement secure coding practices across all services
- Operate within regulated environments (PCI DSS, PSD2, SCA)
Collaboration:
- Collaborate closely with engineers, product teams, and stakeholders
- Contribute to technical discussions and promote engineering best practices
- Support quality assurance across testing, delivery, and system reliability
Requirements:
- Proven experience as a Senior or Principal Java Engineer in hands-on roles
- Expertise in Java 17+ with Spring Boot or Micronaut frameworks
- Experience with, or willingness to learn, Kotlin
- Strong understanding of Kafka, event-driven systems, and microservices
- Experience with payment systems, including PSPs, fraud prevention, tokenisation, and settlement
- Cloud experience, preferably with Azure
- Hands-on experience with Kubernetes, Terraform, and CI/CD pipelines
- Knowledge of regulated environments (PCI DSS, PSD2, SCA)
- Experience in retail or high-transaction environments is advantageous
What's on Offer:
- Six-month contract outside IR35, with potential extension
- Hybrid working model: three days per week on-site at Paddington
- Opportunity to work on high-scale, business-critical platforms within a leading retail organisation
Take the next step in your engineering career by joining a team that values technical excellence and innovation in payment technology.
Reference: 120430
INDTEDA
