Senior Java Developer (AWS, Java, API) – Sussex – Hybrid

Senior Java Developer (AWS, Java, API) – Sussex – Hybrid Daily rate: £500 – £700 (inside IR35)
Duration: 6 months Hybrid: 2 days a week on site (tues, weds) Start: ASAP  
My client is looking for a Senior Software Developer (AWS/Java) to join the Digital Development & Delivery team. You will play a key role in designing, developing, and maintaining secure, scalable, and cloud-native Java microservices, primarily hosted on AWS, integrating with both internal and third-party systems.
Collaborating closely with technical leads, platform engineers, QA, and product teams, you will follow best practices in software design, observability, security, and DevOps principles. You will also contribute to L3 support activities, ensuring the stability and reliability of production systems.
Requirements: 5+ years of professional backend development experience
Strong understanding of Object-Oriented Programming principles and familiarity with Functional Programming
Proficiency in Java (v8 – v24) and dependency injection frameworks
Knowledge of software design patterns
Understanding of microservices architecture and event-driven patterns
Familiarity with other JVM languages
Hands-on experience with AWS cloud services (e.g., Lambda, API Gateway, DynamoDB, ECS, S3)
Experience developing RESTful APIs
Exposure to SOAP and GraphQL services
Familiarity with CI/CD pipelines (e.g., Jenkins, GitHub Actions, AWS CodePipeline)
Knowledge of unit, integration, and automation testing
Awareness of security best practices, including OAuth2/JWT authentication
Awareness of SQL and NoSQL (e.g., OpenSearch)
Familiarity with industry-specific systems (e.g., GDS) is advantageous
Partner and Vendor Teams (onshore and offshore) Backend Service Development Design, build, and maintain secure, high-performance Java-based microservices
Implement RESTful APIs and GraphQL integrations
Ensure services are cloud-native, scalable, and resilient in AWS Code Quality, Testing, and Best Practice Write clean, maintainable code following internal coding standards
Develop automated tests (unit, integration, performance)
Participate in peer code reviews and technical discussions Operational Support and Continuous Improvement Support production systems through L3 incident triage and root cause analysis
Monitor service health using observability tools
Identify opportunities for refactoring and performance improvements Collaboration and Agile Delivery Work with Technical Leads, QA Engineers, and Product Owners to deliver sprint goals
Contribute to estimation, design discussions, and documentation
Participate in DevOps practices including CI/CD and deployments Security, Compliance, and Observability Develop secure APIs and backend services following best practices
Embed monitoring, logging, and tracing into services
Ensure solutions meet organisational security and compliance standards *Rates depend on experience and client requirements