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# Contract Software Engineer (Java & Kotlin)

- **Company:** Spectrum IT Recruitment
- **Location:** London, UK
- **Experience:** Expert
- **Contract:** Temporary contract
- **Skills:** Java (Programming Language), Agile Methodology, Amazon Web Services, Code Review, Continuous Integration, Distributed Systems, Gradle, PostgreSQL, Enterprise Messaging Systems, Software Construction, Spring-boot, Software Application Programming, Reliability of Systems, Backend, Kotlin, Event Driven Architecture, Containerization, Apache Kafka, Restful APIs, Docker, Microservices
- **Published:** August 26, 2026
- **Apply:** https://www.collegerecruiter.com/job/2815164583-contract-software-engineer-java--kotlin

## About the Role

* 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.

## Description

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.


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