Principal Mobile Engineer - Core Tech

Office location

Cambridge, UK – This position offers flexible working options, including predominantly remote work. Applicants should be based (or willing to relocate) within a comfortable commuting distance of our office to attend onsite as required.

Are you an experienced mobile engineer with a track record of leading large-scale technical initiatives and shaping mobile architecture across complex products?

As a Principal Mobile Engineer, you’ll take ownership of mobile engineering direction across critical player-facing systems. From initial player onboarding through to ongoing engagement, you’ll define and deliver scalable, secure mobile solutions that support key journeys across the Rune Scape franchise. Operating across multiple teams and domains, you’ll drive technical strategy, guide architectural decisions, and ensure delivery of high-quality mobile systems that meet the demands of a global player base.

• Own and drive mobile engineering initiatives across multiple projects, ensuring alignment with product goals and long-term technical strategy.
• Define and evolve mobile architecture across iOS and Android, ensuring scalability, performance, and maintainability.
• Lead the delivery of complex technical solutions, coordinating across teams and managing dependencies at a system level.
• Establish and uphold engineering standards across mobile development, including code quality, testing, and deployment practices.
• Identify and drive improvements to systems, services, and engineering processes to support reliable, scalable delivery.
• Work closely with backend, product, and platform teams to ensure seamless integration across services and user journeys.
• Guide technical decision‑making, balancing short‑term delivery with long‑term system health and evolution.

• Proven track record leading large-scale mobile engineering initiatives within production environments.
• Deep expertise in native mobile development across iOS (Swift / Objective‑C) and Android (Kotlin / Java).
• Strong experience defining and evolving mobile architecture integrated with backend microservices.
• Strong understanding of the software development lifecycle, including CI/CD, testing, and release practices.
• Experience operating across teams to manage technical direction, dependencies, and delivery outcomes.
• Advanced debugging, performance optimisation, and system‑level problem‑solving capability.
• Experience with C++ is an advantage.

• Private Healthcare, including Dental Plan.
• Discretionary annual performance bonus.
• Minimum 6% Pension contributions.
• Life Insurance.
• Enhanced family leave policies from day 1.
• Flexible working hours.
• 25 days annual leave + Bank holidays & the option to buy/sell holidays + so much more!

We are committed to providing equal opportunities and creating an environment where everyone can thrive. We welcome applications from all backgrounds, and we recruit, develop, and promote based on merit and ability. If you require any reasonable adjustments to support you during the recruitment process, please let us know when you’re invited to interview.