INTERIM Senior Kotlin Engineer

Interim Senior Kotlin Engineer - £630 p/d (Inside IR35)

Contract | London (Hybrid) | Investment Banking Technology

We are seeking an experienced Interim Senior Kotlin Engineer to join a high-performing front-office engineering team delivering a next-generation cloud-native issuance platform for global capital markets.

This platform is replacing a legacy book building system used by investment banking teams worldwide and supports high-volume, real-time workflows during critical trading windows. The engineering environment is collaborative, fast-paced, and strongly aligned to Extreme Programming (XP) principles.

This is a hands‑on senior engineering position focused on designing, building, and evolving backend services in Kotlin within a modern cloud‑native architecture.

You will work closely with engineers, product specialists, and business stakeholders to deliver resilient, scalable solutions that support real‑time issuance and allocation workflows.

The role places strong emphasis on:

• Mob programming
• Collective ownership

• Design, develop, and maintain backend services in Kotlin
• Contribute to event‑driven and event‑sourced platform architecture
• Collaborate within mob programming sessions as a primary delivery model
• Deliver high‑quality, well‑tested, maintainable code
• Support and improve production systems with strong reliability requirements
• Participate in CI/CD and SDLC practices within an enterprise environment
• Work closely with stakeholders to deliver incremental business features
• Use incidents and operational feedback to improve system resilience and design

• Strong commercial experience building backend services using Kotlin
• Deep understanding of event‑driven and/or event‑sourced architectures
• Extensive experience with XP engineering practices, including:
  • Mob programming
  • Test‑driven development (TDD)
  • Continuous refactoring
  • Clean code principles
• Strong cloud engineering experience within GCP environments, including:
  • GKE and/or Cloud Run
  • Cloud SQL
  • Memory store
  • Artifact Registry
  • Cloud Logging
  • Key Management
• Experience working within regulated or enterprise‑scale environments
• Comfortable supporting high‑availability production systems
• Strong communication and collaboration skills
• Experience with in capital markets, trading, or real‑time financial platforms
• Exposure to front‑office engineering environments
• Experience working on distributed systems handling high‑throughput workflows

You will join a collaborative engineering culture focused on:

• Shared ownership
• Continuous learning

This is an opportunity to work on a business‑critical platform used globally within a modern cloud‑native engineering environment.

Applicants must hold current and valid UK Right to Work