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# Senior Client Developer

- **Company:** LEGO Digital Play
- **Location:** London, United Kingdom
- **Experience:** Expert
- **Salary:** £39,150
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Amazon Web Services, Automation of Tests, C Sharp (Programming Language), Code Review, Software Debugging, Google Cloud, Firebase, Software Library
- **Published:** November 7, 2026
- **Apply:** https://www.adzuna.co.uk/jobs/details/5956245778

## About the Role

* Substantial experience developing games in Unity with C#.

 * A track record of shipping at least one mobile title.

 * Experience working in large, long-lived codebases.

 * Current, hands-on use of AI-powered coding assistants to speed up development, code review and testing.

 * Strong knowledge of mobile device performance, including CPU and GPU usage, memory, loading times and stability.

 * A track record of building systems or infrastructure that a game depends on to run.

 * An active interest in advances in mobile games, AI tools and third-party technology.
Preferred Qualifications

 * Experience with off-the-shelf live-ops platforms.

 * Experience with cloud providers such as Firebase, Google Cloud Platform or AWS.

 * Confidence giving feedback on both the technical and creative sides of prototypes.

 * A broad understanding of modern mobile game development, and a willingness to challenge existing ways of working.

## Description

* Build game features end to end, working with designers to take each feature from idea to players.

 * Build, debug, ship and monitor features in the mobile client.

 * Improve shared client code libraries alongside the wider client development team.

 * Create and maintain AI-assisted automation that makes development and operations workflows more efficient.

 * Build supporting infrastructure, including automated testing, integration with live-ops services and performance metrics.

 * Analyse and fix key areas of mobile client performance.

 * Recommend improvements based on the metrics gathered through tooling.

 * Own the systems you build: design them with the right colleagues, then maintain and improve them over time.