Senior Kotlin Engineer (XP, GCP) - Investment Banking - London/HybridDaily rate: £600 - £800 (inside IR35) Duration: 6 months Start: ASAPMy client is looking for an experienced Senior Kotlin engineer to support and extend a cloud-hosted platform used for bookbuilding issuances within Investment Banking Capital Markets. You will join a high-calibre London-based Front Office engineering team working on a next-generation issuance platform replacing a Legacy bookbuilding system.This is a hands-on engineering role with a strong emphasis on Extreme Programming (XP) practices, including mob programming, test-driven development, and continuous refactoring. Engineers are expected to contribute across development, integration, and production support, collaborating closely to maintain high standards of code quality, system reliability, and performance.Required andamp; Desirable SkillsStrong commercial experience building Back End services using KotlinExperience with event-sourced and event-driven architecturesDeep familiarity with XP practices, including:Mob programming as a primary way of workingTest-driven development (TDD)Continuous refactoring and clean code principlesCloud experience with GCP, including:GKE and/or Cloud RunCloud SQL and Memory storeArtifact Registry and Cloud LoggingKey ManagementExperience with CI/CD and SDLC in regulated or enterprise environmentsComfortable working on production systems requiring high availability and accuracyEngineers in this role:Work ..... full job details .....