Mid Kotlin/Java Server-Side Engineer

Mid weight Kotlin/Java Server-Side API Engineer - Contract Opportunity - London Hybrid

NO SPONSORSHIP OFFERED

We are looking for a Server-Side Engineer to help build and enhance the service layer (Backend-for-Frontend) that powers large-scale mobile applications used by millions of global customers. This role is ideal for someone who enjoys solving complex engineering challenges, working with modern technologies, and contributing to high-quality Back End systems that directly impact user experience.

You'll be joining a collaborative team of engineers, product managers, designers, and QA specialists, working together to deliver fast, reliable APIs that support feature-rich mobile app experiences.

• Develop and maintain Backend-for-Frontend (BFF) services that support large-scale mobile applications.
• Use Kotlin (primary) and Java (secondary) to build clean, maintainable, well-tested Back End components.
• Work closely with cross-functional teams to implement new features and improve existing functionality.
• Contribute ideas, share best practices, and help drive continuous improvement within the engineering team.
• Apply and responsibly leverage AI/LLM-based development tools to enhance productivity, accelerate learning, and improve code quality.
• Participate in code reviews, technical discussions, and architectural decisions.

• Strong foundation in JVM Back End engineering, with hands-on experience in Kotlin and Java (approx. 70/30 split).
• Used AI tools commercially and and happy to discuss this in interviews.
• Enjoys tackling challenging problems and writing clean, well-structured, and maintainable code.
• Curious, proactive, and comfortable sharing ideas in a collaborative environment.
• Passionate about high-quality Back End services that improve mobile user experiences.
• Familiar with modern development tools and comfortable using AI-assisted workflows responsibly.

• Kotlin (primary language)
• Java
• Gradle
• REST APIs
• GraphQL

London, UK

280.00 - 300.00 GBP Daily

Trading as TEKsystems. Allegis Group Limited, Bracknell, RG12 1RT, United Kingdom. No. 2876353. Allegis Group Limited operates as an Employment Business and Employment Agency as set out in the Conduct of Employment Agencies and Employment Businesses Regulations 2003. TEKsystems is a company within the Allegis Group network of companies (collectively referred to as "Allegis Group"). Aerotek, Aston Carter, EASi, Talentis Solutions, TEKsystems, Stamford Consultants and The Stamford Group are Allegis Group brands. If you apply, your personal data will be processed as described in the Allegis Group Online Privacy Notice available at our website.

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