Staff Mobile Engineer

About the Role

As a Senior / Staff Mobile Engineer at Moonshot, you'll lead the next chapter of our iOS and Android trading experience. You'll own the architecture, design system, and engineering practices for our Flutter app, similar to senior mobile engineers at high-scale fintech and consumer apps. Owns highly interactive trading experiences (live prices, charts, order tickets, order history, notifications, portfolio views) with strong performance/reliability; two archetypes - Design System & UX Leader or Growth & Analytics Mobile Lead. You'll ship highly interactive, performant trading experiences while building the foundations (testing, analytics, feature flags) that let the entire team move quickly and safely.

Key Responsibilities

• Own the architecture and long-term evolution of Moonshot's Flutter app across iOS and Android.
• Design, implement, and maintain a company-wide mobile design system and component library, in close collaboration with Design.
• Build highly interactive trading experiences: live prices, charts, order tickets, order history, notifications, and portfolio views.
• Drive mobile performance and reliability: profiling, optimizing frame rendering, managing memory/network usage, and minimizing crashes.
• Implement and maintain automated testing (unit, widget, integration) and help define release and QA processes.
• Collaborate with Product and Growth to integrate analytics, A/B testing, feature flags, and event tracking directly into the app.
• Partner with Backend/Platform engineers on API design, data models, error handling, and resilience (retries, fallbacks, offline behaviour).
• Lead by example through code reviews, design docs, and mentorship, raising the bar for mobile excellence.
• Participate in on-call rotations for mobile-related incidents and drive root-cause fixes.

Requirements

• 6-10+ years mobile dev; 3+ years Flutter or similar (React Native/Kotlin/Swift acceptable even <3 years Flutter with ramp-up)
• Ownership of large-scale consumer apps with performance/crash rates ownership.
• Strong understanding of mobile architectures (state management, navigation, modularization) and their tradeoffs.
• Demonstrated experience building or leading design systems / UI libraries in Flutter or other frameworks.
• Solid engineering fundamentals: testing, CI/CD for mobile, monitoring, and release management.

Bonus Skills

• Strong collaboration skills and experience mentoring other engineers.
• Deep interest in interaction quality, animations, consistency, and accessibility.
• Owns design system, component library, and design-engineering collaboration.
• Focused on instrumentation, A/B test infra, feature flags, and in-app experiment guardrails.
• Works very closely with Growth PM and analytics.
• Built that are used at complex Flutter apps significant scale.
• Experience designing component libraries / design systems.
• Performance and reliability discipline: profiling, crash triage, defensive networking.