Senior Mobile Engineer

Fuse Energy, LLC; Greater London; On-site; GBP 85,000 - 120,000; Full time

Benefits offered by this job

Equity sign-on bonus

Biannual bonus

Fully expensed tech

Paid annual leave

Office breakfasts and dinners

Job summary

Fuse Energy, LLC in London is seeking experienced Mobile Engineers to join a small, high-ownership team. You will own features end-to-end, from customer-facing product to internal tools, shipping consumer-facing AI features on mobile using Swift or Kotlin across iOS and Android.

You'll work with a tight team to design and deliver polished, scalable mobile apps, collaborating with designers and backend engineers, and taking responsibility for code quality, testing, and production readiness in a

Qualifications

• 5+ years building mobile apps on iOS and Android.
• Proficient in Swift or Kotlin with cross‑platform capability.
• Experience shipping consumer AI features on mobile.

Responsibilities

• Design, build, and maintain mobile apps for iOS and Android.
• Own features end-to-end from idea to production.
• Collaborate with designers to ensure high-quality UI/UX.
• Ship consumer-facing AI features on mobile.
• Contribute to scalable, maintainable mobile codebases.
• Test, debug, and resolve issues to ensure stability.
• Troubleshoot production issues for smooth experience.

Skills

5+ years experience

Swift or Kotlin

UI/UX craft

End-to-end ownership

RESTful APIs

Push notifications

Security fundamentals

Job description

We're hiring Mobile Engineers to join a small, high-ownership team in our London office. This isn't a role where you'll be handed fully-specced tickets, you'll own features end-to-end, from customer-facing product to internal tools, including shipping consumer-facing AI features into production on mobile. You'll work in Swift and Kotlin across iOS and Android alongside a tight team of mobile and web engineers, on everything from expansion into new markets to the polish that makes an app feel effortless. Our infrastructure and backend are already excellent; we're looking for mobile engineers who bring the same bar of craft and ownership to match.

Responsibilities

• Design, build, and maintain responsive, reusable, and reliable mobile applications for iOS and Android platforms
• Own features end-to-end, from shaping the product idea through to shipping and iterating in production
• Work closely with designers to implement high-quality UI/UX and ensure design consistency, with a real focus on craft and polish
• Ship consumer-facing AI features into production on mobile, from on-device ML to in-app AI assistants
• Contribute to architectural decisions to ensure scalability, maintainability, and flexibility of the mobile codebase
• Test, debug, and resolve issues to maintain app stability and reliability
• Troubleshoot production issues and provide timely resolutions to ensure smooth user experiences

Qualifications

• 5+ years of professional experience building mobile applications for iOS and Android
• Proficiency in Swift or Kotlin, with deep expertise in at least one platform and the range to work across both
• Strong grasp of mobile UI/UX principles and best practices for creating intuitive, responsive experiences, with a real eye for craft and detail
• A track record of owning features end-to-end and contributing product ideas, not just executing specs
• Hands‑on experience integrating RESTful APIs with mobile applications
• Familiarity with push notifications, messaging services, and related mobile frameworks
• Understanding of mobile security fundamentals and ability to implement secure data handling

Benefits

• Competitive salary and an equity sign‑on bonus
• Biannual bonus scheme
• Fully expensed tech to match your needs
• Paid annual leave
• Breakfast and dinner allowance for office based employees