Senior Kotlin Engineer – Event Streaming/Sourcing (London)

About the role

Our client, a leading investment‑banking platform, is seeking two Senior Kotlin Engineers to join a cloud‑hosted team in London. The role is hybrid (two days onsite) and focuses on building reliable, high‑performance backend services for front‑office users. You will work in a fast‑paced environment, delivering features quickly while maintaining rigorous engineering standards.

Key responsibilities

• Design, develop, test and maintain Kotlin‑based backend services.
• Implement and support event‑driven architectures, including event sourcing and streaming.
• Participate in Agile/XP practices such as pair programming, mob programming and test‑first development.
• Build and maintain CI/CD pipelines and deploy services to cloud environments.
• Continuously refactor code to ensure high quality, reliability and maintainability.
• Contribute to architectural and technical design discussions.
• Collaborate closely with front‑office stakeholders and cross‑functional teams to deliver solutions within tight timelines.

Required profile

• Strong commercial experience developing production‑grade Kotlin applications (non‑Android).
• Proven expertise in Test‑Driven Development and test‑first approaches.
• Hands‑on experience with event‑driven systems, including event streaming or event sourcing.
• Experience building CI/CD pipelines and working with cloud platforms (AWS, GCP or Azure).
• Track record of refactoring legacy code and maintaining clean, maintainable systems.
• Experience in Agile/XP environments, ideally including mob programming.
• Excellent communication skills for engaging with business and front‑office stakeholders.

Required skills

• Kotlin
• Test‑Driven Development (TDD)
• Event streaming (e.g., Kafka)
• Event sourcing
• CI/CD tools
• Cloud platforms (AWS, GCP, Azure)
• Docker
• Kubernetes
• Observability and monitoring tools
• Incident response practices