Contract Senior Software Engineer (Java or Python) Inside IR35Contract length: 6 months (with potential to extend)Location: LondonWorking Environment: On-siteYou will be joining a private equity firm as a senior software engineer, to work across the following responsibilities:Develop and support PandL, accounting, and returns-calculation applications across trading booksBuild and extend our Client Reporting FrameworkAdd instrument and asset class coverage in our Trade Repository systemManage data exchange with third-party vendors via SFTP and AWS S3Use AI coding assistants (Claude, Cursor, GitHub Copilot) to compress delivery timelines while maintaining full code ownership and quality accountabilityCollaborate with quant researchers and traders to translate complex financial requirements into auditable, production-grade codeProvide production support, working with Platform and SRE teams as needed Key Requirements: Technical:8+ years commercial experience in Python or Java across the full development lifecycle5+ years in financial services (buy-side strongly preferred)Solid relational database skills; MS SQL Server a strong plusSnowflake experience requiredFamiliarity with AWS (S3, Lambda, EC2, Glue or similar)Proficiency with Git, CI/CD pipelines, and observability tooling (e.g. Datadog)AI and Tooling:Proven, hands-on experience shipping production code using AI coding assistants such as Claude, Cursor, or GitHub CopilotDemonstrable examples where AI tooling reduced delivery