Mobile iOS Engineer

SpaceX Super Intelligence; Greater London; On-site; GBP 107,000 - 262,000; Full time

Benefits offered by this job

Healthcare coverage

Dental coverage

Cash plan

Income protection

Life insurance

Employee equity

Job summary

SpaceXSI is seeking an exceptional iOS engineer to join a small, high-impact team dedicated to creating the world’s most valuable AI application, judged by the impact it delivers to users. You’ll shape cutting‑edge mobile experiences, blending technical mastery with product brilliance.

You’ll own features end‑to‑end, from architecture to App Store deployment, and collaborate with AI researchers to deploy models globally, delivering fast, polished experiences on iOS.

Qualifications

• Expert in Swift with SwiftUI and UIKit.
• Experience in performance optimization for memory, CPU, and GPU.
• Skilled in designing and shipping pixel-perfect mobile UIs for AI applications.
• Proficient in concurrency and reactive programming (Combine).
• Built high-throughput integrations with APIs (REST, gRPC) and AI model outputs.
• Capable of owning complex features end-to-end, from architecture to App Store deployment.

Responsibilities

• Dream up and craft delightful, intuitive user experiences that redefine how people interact with AI on mobile.
• Obsess over every pixel, animation, and interaction to ensure the experience feels magical and seamless.
• Build blazing-fast, highly performant systems where every millisecond counts.
• Drive technical and product decisions, collaborating with AI researchers and engineers to deploy state-of-the-art models globally.

Skills

Swift

SwiftUI

UIKit

Performance optimization

Concurrency

Combine

REST APIs

gRPC

End-to-end ownership

Apple ecosystem

Tools

AVFoundation

Rust

Xcode

Job description

SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where we are not. Today, SpaceX is actively developing the technologies to make this possible, with the ultimate goal of making life multiplanetary and expanding consciousness to the stars.
SpaceXSI is building Super Intelligence to help humanity understand the universe. Our teams are building the full Super Intelligence stack: from our Colossus supercomputers, to Grok models, to our suite of applications, including Grok Bot, Grok Build, Grok Imagine, Grok Voice, and X. We're creating a powerful flywheel where more compute trains better models, better models power more useful products, and what we learn from people using those products shapes what we build next.

SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where we are not. Today, SpaceX is actively developing the technologies to make this possible, with the ultimate goal of making life multiplanetary and expanding consciousness to the stars.
SpaceXSI is building Super Intelligence to help humanity understand the universe. Our teams are building the full Super Intelligence stack: from our Colossus supercomputers, to Grok models, to our suite of applications, including Grok Bot, Grok Build, Grok Imagine, Grok Voice, and X. We're creating a powerful flywheel where more compute trains better models, better models power more useful products, and what we learn from people using those products shapes what we build next.

ABOUT THE ROLE:

We’re seeking an exceptional iOS engineer to join a small, high-impact team dedicated to creating the world’s most valuable AI application, judged by the impact it delivers to users. You’ll shape cutting‑edge mobile experiences, blending technical mastery with product brilliance.

RESPONSIBILITIES:

• Dream up and craft delightful, intuitive user experiences that redefine how people interact with AI on mobile.
• Obsess over every pixel, animation, and interaction, ensuring the experience feels magical and seamless.
• Build blazing‑fast, highly performant systems where every millisecond counts.
• Drive technical and product decisions, collaborating with AI researchers and engineers to deploy state‑of‑the‑art models globally.

BASIC QUALIFICATIONS:

• Expert in Swift, with deep knowledge of SwiftUI and UIKit.
• Proficient in performance optimization—memory, CPU, GPU—using low‑level tools to deliver blazing‑fast systems.
• Experienced in designing and shipping intuitive, pixel‑perfect mobile UIs that redefine how users interact with AI.
• Skilled in concurrency and reactive programming (Combine) for responsive, real‑time apps.
• Built high‑throughput integrations with APIs (REST, gRPC) or AI model outputs, ensuring seamless data flow.
• Capable of owning complex features end‑to‑end, from architecture to App Store deployment, with a focus on speed and scalability.

PREFERRED SKILLS AND EXPERIENCE:

• Deep expertise in the Apple ecosystem and related development tools.
• Rust for working with our backend components.
• AVFoundation for real‑time audio processing.
• Track record of shipping standout apps or standout features within apps.
• Deep expertise in iOS development, particularly with Swift. We seek individuals who operate at the highest levels of their craft.
• Excel at delivering results swiftly, often in a fraction of the time others require. Speed is a core value at SpaceXSI—we must act decisively to succeed.
• Sharp product sense, with an ability to empathize with users, anticipate their needs, and translate that into features that delight and deliver value.

COMPENSATION AND BENEFITS:

£107,000 - £262,000 GBP

Base salary is just one part of our total rewards package at SpaceXSI, which also includes equity, comprehensive healthcare and dental coverage, cash plan, income protection, life insurance, and various other discounts and perks.

SpaceXSI is an equal opportunity employer. For details on data processing, view our