Contract Software Engineer (Java & Kotlin)

Senior Java & Kotlin Backend Engineer

Location: London (Hybrid - Wednesday office attendance required) Contract: Initial 2 months IR35: Outside IR35 Start Date: ASAP

The Role

We’re working with a leading technology organisation seeking an experienced Senior Java & Kotlin Backend Engineer to join their engineering team on an initial two-month contract.

This role offers the opportunity to contribute to greenfield backend development, building scalable, cloud-native microservices within a modern engineering environment. You’ll work alongside cross-functional teams to design, develop and deliver high-quality backend solutions that are secure, reliable and built for scale.

Key Responsibilities

• Design, develop and maintain backend services using Java and Kotlin.
• Build and enhance RESTful APIs within a microservices architecture.
• Develop secure, scalable and high-performance applications.
• Collaborate with Product Managers, Engineers and technical stakeholders to deliver new features.
• Participate in code reviews and contribute to engineering best practices.
• Improve system reliability, performance and scalability.
• Work with cloud-native technologies and modern deployment practices.
• Support production systems and contribute to continuous improvement initiatives.

Essential Skills & Experience

• Strong commercial experience with Java and Kotlin.
• Proven experience developing applications using Spring Boot.
• Strong understanding of microservices architecture.
• Experience designing and building REST APIs.
• Commercial experience with Kafka or similar messaging technologies.
• Experience with PostgreSQL.
• Experience working with AWS cloud services.
• Hands-on experience with Docker and containerised applications.
• Strong understanding of software engineering best practices, testing and CI/CD.
• Excellent communication and problem-solving skills.

Desirable

• Experience with Gradle.
• Experience working within Agile development teams.
• Knowledge of distributed systems and event-driven architectures.

Contract Details

• Initial 2-month contract.
• Outside IR35.
• Hybrid working with office attendance in London every Wednesday.
• Immediate start available.

Spectrum IT Recruitment (South) Limited is acting as an Employment Business in relation to this vacancy.

• Strong commercial experience with Java and Kotlin.
• Proven experience developing applications using Spring Boot.
• Strong understanding of microservices architecture.
• Experience designing and building REST APIs.
• Commercial experience with Kafka or similar messaging technologies.
• Experience with PostgreSQL.
• Experience working with AWS cloud services.
• Hands-on experience with Docker and containerised applications.
• Strong understanding of software engineering best practices, testing and CI/CD.
• Excellent communication and problem-solving skills.

Desirable

• Experience with Gradle.
• Experience working within Agile development teams.
• Knowledge of distributed systems and event-driven architectures.