Job Description

Why this job matters
Cloud Native Java Developer - To Individually contribute and Drive transformation of our existing Java microservices deployed on Amazon Elastic Kubernetes Service (EKS) to serverless AWS Lambda functions , below are the Roles and Responsibilities
What you'll be doing
Key Responsibilities

• Develop and deploy serverless applications using Quarkus/Spring Boot and AWS Lambda
• Build RESTful APIs and event-driven microservices using cloud-native patterns
• Optimize cold-start performance using GraalVM native images
• Integrate with AWS services such as AWS API Gateway, S3, DynamoDB, CloudWatch and Postgres
• Implement and manage Lambda authorizers (custom and token-based) for securing APIs
• Design and configure AWS API Gateway for routing, throttling, and securing endpoints
• Integrate OAuth 2.0 authentication flows using Azure Active Directory as the identity provider
• Descent Understanding of resilience patterns
• Write unit and integration tests using JUnit, Mockito, and Quarkus testing tools
• Collaborate with DevOps teams to automate deployments using AWS SAM, CDK, or Terraform
• Monitor and troubleshoot production issues using AWS observability tools

Migration Responsibilities

• Analyse existing Spring Boot microservices deployed on Kubernetes to identify candidates for serverless migration
• Refactor services to be stateless, event-driven, and optimized for short-lived execution
• Replace Kubernetes ingress and service discovery with API Gateway and Lambda triggers
• Migrate persistent state and configuration to AWS-native services (e.g., DynamoDB, S3, Secrets Manager)
• Redesign CI/CD pipelines to support serverless deployment workflows
• Ensure performance, cost-efficiency, and scalability in the new architecture
• Document migration strategies, patterns, and best practices for future reference

Technical Proficiency
Strong industry expereince of 4+ years with command of Java 8+, with deep understanding of:

• Functional interfaces (Function, Predicate, Supplier, Consumer)
• Streams API, lambda expressions, and Optional
• Proficiency in Java concurrency, including:
• Thread management, Executor Service, Completable Future, and parallel streams
• Designing thread-safe components and understanding concurrency pitfalls
• Understanding of AWS EKS (Elastic Kubernetes Service) , Docker Containers and Kubernetes fundamentals:
• Experience with resource requests and limits, pod autoscaling, and K8s networking
• Familiarity with transitioning workloads from EKS to serverless environments

About us
BT Group was the world's first telco and our heritage in the sector is unrivalled. As home to several of the UK's most recognised and cherished brands - BT, EE, Openreach and Plusnet, we have always played a critical role in creating the future, and we have reached an inflection point in the transformation of our business.
Over the next two years, we will complete the UK's largest and most successful digital infrastructure project - connecting more than 25 million premises to full fibre broadband. Together with our heavy investment in 5G, we play a central role in revolutionising how people connect with each other.
While we are through the most capital-intensive phase of our fibre investment, meaning we can reward our shareholders for their commitment and patience, we are absolutely focused on how we organise ourselves in the best way to serve our customers in the years to come. This includes radical simplification of systems, structures, and processes on a huge scale. Together with our application of AI and technology, we are on a path to creating the UK's best telco, reimagining the customer experience and relationship with one of this country's biggest infrastructure companies.
Change on the scale we will all experience in the coming years is unprecedented. BT Group is committed to being the driving force behind improving connectivity for millions and there has never been a more exciting time to join a company and leadership team with the skills, experience, creativity, and passion to take this company into a new era.
A FEW POINTS TO NOTE:
Although these roles are listed as full-time, if you're a job share partnership, work reduced hours, or any other way of working flexibly, please still get in touch.
We will also offer reasonable adjustments for the selection process if required, so please do not hesitate to inform us.
DON'T MEET EVERY SINGLE REQUIREMENT?
Studies have shown that women and people who are disabled, LGBTQ+, neurodiverse or from ethnic minority backgrounds are less likely to apply for jobs unless they meet every single qualification and criteria. We're committed to building a diverse, inclusive, and authentic workplace where everyone can be their best, so if you're excited about this role but your past experience doesn't align perfectly with every requirement on the , please apply anyway - you may just be the right candidate for this or other roles in our wider team.

Skills Required