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 a principal‑level mobile engineer ready to set the technical direction for mobile across one of the world’s most iconic gaming franchises?

As a Principal Mobile Engineer in our Player Gateway team, you’ll own the mobile architecture and engineering strategy that shapes how players first experience Jagex titles – from their very first visit through to becoming active members of our game communities.

This is a role with genuine organization‑wide impact: your technical decisions will set the standards and patterns that engineers across multiple teams build on.

You’ll lead the most complex, high‑stakes mobile initiatives from concept through to production, influence engineering strategy beyond your immediate team, and raise the bar for mobile engineering across the discipline – all while helping the next generation of engineers grow.

What you’ll be doing: Own the technical direction and architecture for mobile initiatives within the Player Gateway team, influencing engineering standards and strategy across the wider discipline.

Lead the delivery of our largest, most complex mobile initiatives – breaking down ambiguity, de‑risking delivery, and defining the approaches other engineers follow.

Drive long‑term improvements to systems, services, and ways of working that extend well beyond a single team, shaping the future of mobile at Jagex.

Contribute across the full Software Development Lifecycle, delivering secure‑by‑design, production‑ready code backed by automated testing, peer review, and reliable deployment.

Lead build/buy evaluations and architectural proposals, ensuring technical solutions meet both product needs and Jagex’s engineering standards.

Raise the engineering bar across the mobile discipline through coaching, mentoring, and championing best practice – multiplying the effectiveness of those around you.

Participate in an on‑call rotation to troubleshoot and resolve production issues when required.

What we’re looking for: Demonstrable expertise in native mobile development across both i OS (Swift / Objective‑C, Xcode, Instruments) and Android (Kotlin / Java, Android Studio, profilers), with a deep understanding of OS‑level constraints including app lifecycle, permissions, backgrounding, and store policies.

Proven ability to set and own technical direction and mobile architecture across multiple teams or an engineering discipline.

Track record of leading large, ambiguous, or cross‑team technical initiatives from concept through to production, with minimal direction.

Demonstrated experience influencing technical strategy and building consensus across teams and senior stakeholders without direct authority.

Proven ability to raise engineering standards across a discipline through coaching, technical leadership, and championing best practice.

Strong experience with automated testing, CI/CD systems (e. g.

Git, Bitbucket Pipelines, Bamboo), debugging, profiling, and mobile performance optimisation at scale.

Experience with A/B testing frameworks, analytics SDKs, and collaborating with UX designers to deliver streamlined player experiences is advantageous.

Experience with C++ and game systems is a plus.

What we offer: When you join Jagex you can look forward to a generous Perks