Principal Java Developer (Payments)

TL;DR

Principal Java Developer (Payments): Design, develop, and optimize low-latency, high-throughput backend systems using Java with an accent on performance, memory optimization, and scalable microservices. Focus on building RESTful APIs, integrating with cloud environments like AWS and OpenShift, and driving architectural improvements for secure payment workflows.

Location: Hybrid work model in London, UK.

Company

Fast-growing business and technology consulting company co-founded in 2019, serving Fortune 500 clients with custom engineering services in digital transformation.

What you will do

• Design, develop, and optimize low-latency, high-throughput backend systems using Java.
• Build and maintain RESTful APIs and microservices for secure payment workflows.
• Work with messaging standards, MongoDB, and other datastores for real-time data management.
• Deploy, monitor, and scale applications in Red Hat OpenShift and AWS environments.
• Collaborate with DevOps, Product, and QA teams to deliver production-grade solutions.
• Drive architectural changes, performance tuning, best practices, and mentor peers.

Requirements

• 10+ years of experience in Java development with focus on performance and memory optimization.
• Proficient in MongoDB, Spring, and microservice-based architecture.
• Proven experience with low-latency, high-throughput applications.
• Hands-on experience deploying on Red Hat OpenShift and/or Kubernetes.
• Strong cloud experience with AWS services (ECS, EKS, Lambda, S3, etc.).
• Strong communication skills and bias toward action and opinionated design.

Nice to have

• Familiarity with messaging systems (Kafka, RabbitMQ).
• Prior experience in payments processing, financial services, or banking.
• Exposure to container security and performance tuning on OpenShift.
• Knowledge of payment gateways, ISO 20022, or SWIFT formats.

Culture & Benefits

• Collaborative, fast-paced, engineering-driven culture with autonomy and clean code emphasis.
• Global, diverse, woman-owned team with low 7% attrition rate.
• Referral bonuses for bringing talented friends.
• Emphasis on high-performing teams and opinionated engineering practices.