Principal Java Developer – Major Financial Institution London / Hybrid | Contract | £700-£800 inside IR35 (gross umbrella rate) We’re working with a major financial institution looking to scale out its engineering function with a Principal Java Developer to lead critical systems work. This is a hands-on role within a high-performing team modernising legacy platforms, improving availability, and delivering new functionality across the estate. You’ll be working closely with infrastructure, architecture, and infosec teams to support high-availability production systems. The role also involves guiding CI/CD improvements, REST API design, and steering collaborative technical decisions across squads. What they’re looking for: Proven experience supporting large-scale, business-critical systems Strong background in Java and ideally C# Some front end exposure (Angular ideally but other frameworks considered). Note the role is back end focused. Comfortable working with legacy systems and large enterprise environments Confident leading technical conversations across multiple engineering disciplines Experience with CI/CD pipelines and modern deployment practices Greenfield REST API design including HATEOAS implementation Bonus points for: Angular, React or frontend exposure Familiarity with Snowflake or backend SQL variants This is a great opportunity for an experienced Java Developer to join a prestigious financial player. If you’re someone who thrives in complex environments and enjoys technical leadership alongside delivery, apply now.