Senior Software Engineer - (Java, Pricing API,) - 5 days - Retail - London Day rate: £400 - £500 (inside IR35)Duration: 6 months On site: 5 days per weekStart: Now My client is looking for a Senior Java Developer with 8 - 15 years experience to join the team 5 days a week in their London office. This is an opportunity to work on a mission critical pricing and promotions API that supports over 28 million UK customers weekly, across all platforms with global expansion ahead.This role involves designing and scaling a high-performance, internet-facing API operating across distributed environments. If you enjoy solving complex engineering challenges and building resilient systems at scale, this could be a great fit.What You''ll Be DoingDesigning and building scalable backend systems using Java and the JVM ecosystemDeveloping clean, maintainable code from product requirementsApplying TDD/BDD practices and modern engineering principlesBuilding and maintaining cloud-native infrastructureWorking on highly available distributed systemsTroubleshooting production issues and driving root cause analysisMentoring others and contributing to engineering best practicesExploring and introducing new tools and technologiesTech StackJava Vert.x RxJava Groovy Couchbase Kafka Azure Kubernetes TerraformGitHub Actions CI/CD pipelinesWhat We''re Looking ForStrong experience with Java (8+)Hands-on expertise with cloud platforms (Azure, AWS, etc.)Experience with SQL and NoSQL databasesProven ability to b