Senior Java Developer - Multithreading/caching - sought by leading investment bank based in London - Contract*inside IR35 - umbrella*Key ResponsibilitiesDevelop and maintain high‑performance backend services for complex data processing workloads.Design scalable architectures for large‑volume calculations and data pipelines.Work closely with cross‑functional teams to define and deliver new features.Ensure optimal performance, quality, and reliability across backend services.Diagnose and resolve performance bottlenecks and defects.Follow best‑practice engineering standards, design patterns, and architectural principles.Apply Test‑Driven Development (TDD) in day‑to‑day development.Use static code analysis tools such as SonarQube to maintain clean, high‑quality code.Work efficiently with SQL, data joins, and large/complex datasets.Leverage AI tooling to enhance productivity in coding and system design.Required Skills & Experience8+ years' experience in Java backend development (Java 17+).Degree in Computer Science, Software Engineering, or related field.Strong expertise in Java + Spring Boot / Spring Data / Spring Cloud.Excellent SQL knowledge and experience optimising queries and data models.Strong understanding of in‑memory data loading and efficient join strategies.Deep familiarity with Java tooling (Maven/Gradle, testing frameworks, dependency management).Proven experience building data processing or data‑intensive applications.Solid understanding of modern architectural patterns (Microservices, Event‑Driven Architecture).Strong TDD skills and experience using static code analysis (e.g., SonarQube).Clear communication skills with the ability to explain technical concepts to varied audiences.Nice to HaveCloud experience: AWS / Azure / GCP.Containerisation: Docker, Kubernetes.Distributed processing: Apache Spark / Flink.Please apply within for further details - Matthew Holmes, Harvey NashToFromRecordYes NoAlways use these settings #J-18808-Ljbffr