Mobile Backend Developer (Java / Kotlin)

📍 Manchester (Hybrid – 3 days Onsite)

📄 6-Month Contract | Day Rate: £460 per day (Inside IR35)

Our client, a top global organization, is seeking a Senior Mobile Backend Developer with strong Java/Kotlin and cloud-native microservices experience to join a high-impact financial services programme. This is a hands-on engineering role where you’ll contribute to the design and delivery of secure, scalable backend services powering mobile applications within a distributed cloud environment. As a Senior Application Engineer, you’ll provide deep technical expertise in backend development, working across the full SDLC while promoting best practices such as TDD, BDD, and clean architecture.

Key Responsibilities

• Design and develop distributed, scalable microservices using Java/Kotlin and Spring Boot
• Build secure APIs for mobile applications (OAuth 2.0, secure API design)
• Contribute across all phases of the SDLC (requirements → development → deployment → support)
• Apply event-driven architecture principles
• Promote engineering best practices including TDD / BDD
• Apply design patterns to solve complex technical challenges
• Mentor junior engineers and support knowledge sharing
• Collaborate with technical leads and business stakeholders
• Ensure adherence to IT and Information Security standards

Essential Skills & Experience

• Strong experience building cloud-based backend applications using Java and/or Kotlin
• Hands-on experience with Spring Boot and microservices architecture
• Experience designing secure, scalable APIs (OAuth 2.0)
• Understanding of API design for mobile applications
• Experience working in event-driven architectures
• Strong analytical and problem-solving skills
• Experience working within financial services environments

Desirable

• AWS experience
• Automation testing experience
• Exposure to CI/CD and DevOps practices

If this is relevant, please apply with your CV and we’ll be in touch. Thank you!