Senior Backend Engineer in London

LEGO Digital Play (LDP) will bring the LEGO brand into digital entertainment in new, innovative, and wholly-owned ways. Our mission is to ensure the LEGO Brand remains as powerfully a part of children’s lives in the next 20 years as it has been for the past 60. We aim to reach every kid on the planet, their parents, and adult fans of LEGO—and provide them with meaningful, magical, and playful new experiences. We are in the earliest phases of this new company, offering a unique opportunity to build a new entity for the world's most beloved and trusted brand. Our culture is open, collaborative, intellectually rigorous, and creatively vibrant.

LDP is shaping the future of digital play by taking inspiration from the LEGO Brand’s “system in play” and reimagining it for the digital world. Our portfolio is built on a foundation of safety that will ultimately inspire the builders of tomorrow. We are looking to hire a Senior Backend Engineer to join us on our journey; this is a newly created position based in our HQ in London (WeWork, Waterloo).

Key Responsibilities:

• Design and implement scalable backend systems using cloud platforms such as AWS, supporting high concurrency and global player bases.
• Build and operate distributed services supporting core platform capabilities including player identity, persistence, social systems, matchmaking, and multiplayer services.
• Architect cloud-native systems that scale horizontally and vertically using modern compute models and distributed storage technologies such as NoSQL databases.
• Design server-authoritative multiplayer infrastructure capable of running large numbers of concurrent game simulations reliably and efficiently.
• Architect simulation environments with strong sandboxing and isolation guarantees so that each simulation runs independently.
• Ensure failures, crashes, or performance spikes in one simulation cannot impact other simulations running within the same server instance.
• Develop infrastructure capable of safely packing and scheduling multiple simulation workloads per server instance while maintaining predictable performance and resource isolation.
• Implement resilient and recoverable infrastructure with strong observability, monitoring, and operational tooling.
• Develop systems that protect the platform from abuse and cheating, ensuring fair and safe multiplayer experiences.
• Build load testing and capacity validation systems to verify the scalability and performance of the platform under large-scale traffic.
• Implement infrastructure as code and automated deployment pipelines enabling reliable CI/CD and continuous delivery.
• Establish strong engineering practices including automated testing, integration testing, and performance testing to enable rapid iteration while maintaining system stability.
• Work within a cross-functional team spanning product, design, art, production, and engineering, while partnering with shared technology teams across the organization.
• Collaborate with engine, platform, and gameplay teams to ensure backend systems integrate seamlessly with game runtimes and multiplayer architectures.
• Use AI-assisted development tools and workflows to accelerate development, debugging, and operational insights across the engineering lifecycle.

Qualifications:

• Experience in software engineering building distributed or large-scale backend systems.
• Strong experience designing and operating cloud infrastructure using platforms such as AWS.
• Proven experience building systems that support high-scale services with millions of users or high concurrency workloads.
• Experience designing scalable distributed architectures and working with services-based systems.
• Experience working with distributed storage technologies such as NoSQL databases and large-scale data systems.
• Experience designing reliable real-time multiplayer systems, matchmaking services, or server-authoritative game infrastructures.
• Understanding of simulation lifecycle management, resource scheduling, or sandboxing approaches for running multiple workloads safely on shared infrastructure.
• Experience implementing observability, monitoring, and operational reliability practices for large-scale services.
• Experience designing and running load testing, stress testing, and capacity validation systems.
• Experience implementing infrastructure as code, CI/CD pipelines, and automated testing frameworks.
• Knowledge of security, anti-cheat systems, or protecting online game platforms from abuse is a strong plus.
• Comfortable collaborating across engine, platform, and gameplay teams.
• Experience incorporating AI-assisted development tools into daily engineering workflows.

LEGO Digital Play is committed to inspiring and developing the builders of tomorrow - both in the physical and digital worlds. If you are passionate about shaping the future of interactive play through innovation, technology and programmable systems we invite you to come build the future with us!